I don't know how to thank you enough so I won't even try but thank you times infinity. Okay, I get it now, for a newbie that is. I'll stick to one thread. I have questions about that though. Sometimes I run into a dead end on finding an answer, I post something in here and then I find the answer. Is there a way for me to go back and remove old posts that are now irrelevant or do post need to stay in here to keep others with similar situations informed?
Next question, what I've found several times in here is someone will answer a question and tell me I should try this or that and I find myself in the dunce's corner wondering what they meant or how to preform such a task. I guess I fall guilty as well in the reverse sometimes by not being clear and detailed on what I've done so far. I'll work on that.
I would think that the shop manual would be a go to place for a lot of things but like I posted on another thread, it's not easy to use when there are no page numbers. Someone said something about it being a PDF and that's why no page numbers are on the bottom of the page. Is there another place on line to download or at least view the shop manual? The second obstacle with the manual is once I find the section that applies to me, there's a lot of abbreviations that I guess I'm suppose to know. I do know a lot of them but sometimes, okay, a lot times, I scratch my head and end up not knowing what to do next. Yes, I saw the list of abbreviations in the manual but still found some not listed.
Okay... enough of that. On with what you wrote, one step at a time.
Here's what I just did; on the passenger side of the car, where the actual fuel pump is, I unplugged the 4 wire wiring harness at the fuel pump. With no key in the ignition I put a multimeter into the female sockets of that plug. I looked all over both side of the plug for numbers but didn't see any. So I'll describe it. Looking into the female side of the plug or the side that goes away from the pump I held it with the "attachment bump" on the top. I could look in and see 4 female sockets. I put the positive leg of the meter on the upper left socket and the common leg of the meter in the upper right. I got 12 volts. I tried other combinations but that's the only way I got 12 volts. If I reversed the two meter cables the meter tried to go backwards. I get it, DC volts.
Then I turned the key to 'run' position, not crank of course because I'm by myself. I put the meter cables in the same sockets I had them in before when I got 12 volts. Nothing. Reversed. Nothing. Then I put the positive leg on the lower left and the common on the same place as before, the upper right. I got 12 volts. I hope some of this makes sense.
So, okay, it would seem that there's 12 volts that far down the line, as long as what I saw was correct. Now, next question; should I plug the 4 wire connector back together and check for voltage on those wires another way like stabbing the insulation of those wires with a meter? If so, what am I looking for and where?
How am I doing so far? I'm trying, like you said to take this one step at a time. Next I'll move to checking delays. I've already swapped the one in the trunk with a fog light relay. Nothing. Is there a way to test a relay with a meter.
Thanks again for your help and your time.
Steve

 

Short answer Steve . . . no.
Long answer, and you guessed it . . . so our indiscretions (as well as brilliance) are preserved to edify others.
Often, we learn most from the most puzzling challenges.

Perhaps the lesson here is . . . don't be too hard on yourself; there are no dumb questions so, if you don't understand something, just say so . . . someone will readily explain. However, you can help as you suggest. From this current problem, I'm betting you have learned heaps, not just about this specific problem . . . but how to go about solving it. What resources do I need? What do my forum searches show on this topic? Stuff like acronyms or abbreviations or other technical terms are all explained in the Stickies, while the FAQs and "How To . . ." guides are a mine of info.

The digital PDF file format is now almost universal for service manuals . . . thousands of pages of mixed text and drawings, but you only need to print out those you need for a specific task. Take it our to the car; get grease all over each page; throw it away once done. The key to finding which pages you need . . . is by using the indexed "bookmarks" generally available down the lefthand margin of your computer screen. Want to find a particular control module? Use bookmarks to go to Electrical; click to expand; jump to relevant drawing and . . . Bingo . . . page numbers become irrelevant, coz it jumps you straight to the drawings you need. Check to ensure you have the correct engine size, LHD or RHD, etc.

Hope this helps,

Ken

 

Okay, thanks. Here's my question; what are your thoughts on the readings I was getting from my meter, one with the key on, the other with the key off.
And second, how can I test to see if that 12 volts is passing through that connector and into the canister or better yet, actually getting to the fuel pump itself?
If I remember correctly, there are only 2 wires going to the pump itself but there are 4 wires on that plug. I think I'm going to have to pull that whole device back out of the tank and bench test it somehow. Is there another way? I'm taking the day off work to work on this more. I simply can NOT afford to take this car to the dealer. They want $180 an hour! Thanks again for all of your wisdom. Just tell me where to mail the check.

 

Yes, it makes some sense, but unfortunately, it doesn't help much. Without the same plug in front of me, I have no way of knowing what wires you were measuring. Also, it's very possible that the voltage you were seeing is for the fuel level sensor, not the pump motor.

The best way to identify the wires is by color. See page page 14 for the wiring color codes:


http://www.jagrepair.com/images/Auto...x2032002en.pdf


Wiring Color Codes:
N Brown
O Orange
B Black
S Slate
W White
L Light
K Pink
U Blue
G Green
P Purple
R Red
Y Yellow
BRD Braid

When you have a two-character code, the first character is the primary color, and the second is the stripe or dash on the side. For example, WB is white with a black stripe or dash mark.


In those same wiring diagrams, scroll down to fig. 3.2 to see the fuel pump, near the bottom left. I'm pretty sure the 4-wire connector you had apart is FP4. Note how it's actually split up on the illustration, on either side of the pump, but that's not really accurate. In real life, that's a single connector with multiple contacts, but it's drawn as if separate. If you scroll up one page from the diagram, you will see some text to the right:

Components:

The second column, about halfway down, describes connector FP4 as a 4-way black connector, located "below rear seat cushion".

The two wires feeding the pump are contacts FP4-1 (wire color code GO: green with orange stripe) and FP4-3 (BR: black with red stripe). Those are the wires you should be dealing with.

For all we know, you may have been measuring voltage on the other 2 wires in plug FP4. See fig 07.1 for those 2 wires at the RH fuel level sensor. Contact FP4-2 is for the WR wire (white with red stripe). Contact FP4-4 is for the NR wire (brown with red stripe). Leave those two wires alone. We are currently only concerned with the GO (green with orange stripe) and BR (black with red stripe) wires feeding the fuel pump.






No idea, but per my previous message, let's not worry about the 12 volts feeding the pump. It's super easy to get non-conclusive results that can be misleading. Remember, seeing 12V there isn't proof the power feed is good. It just means it isn't 100% failed, that's all.


No, let's not do that right now. There are many ways to troubleshoot, but I'd like to just pick one method and go with it. I'd like to apply FUSED power directly to the pump input and see if the pump runs and puts out pressure. This will help determine if the problem is electrical or mechanical.




Yes there is a way to test a relay with a meter, but let's not go there right now. Swapping with a known good relay is the easiest and most reliable test.

What I'd like to see is you run these two simple tests, previously listed in this post from another thread:


https://www.jaguarforums.com/forum/s...5/#post1864782


Copied below for your convenience. Remember, you will be dealing ONLY with the two wires feeding the pump - contacts FP4-1 (wire color code GO: green with orange stripe) and FP4-3 (BR: black with red stripe). Those are the wires you should be dealing with. The first test is checking continuity through the pump. If that is good, you will briefly apply FUSED power directly to the pump leads:



"You mentioned already having access to the pump wiring underneath the seat, so I'd go with that. Disconnect the plug for the pump. Turn the ignition off, as you're not checking power to the pump, only continuity through the pump and associated wiring.

Set your meter to ohms and touch the two leads together. You should see very close to zero ohms, possibly a fraction. This is just to test the integrity of the test leads and the accuracy of the meter. Now touch the two leads to the two contacts leading to the fuel pump. This is now measuring the continuity of the pump. I don't know the exact value, but several ohms sounds about right. If you see zero ohms, or close to it, the pump is shorted internally. If you see infinite ohms, or some very high number, that means the circuit inside the pump is broken. Let us know what value you get. Hopefully somebody can chime in with what range is normal. Basically you shouldn't see a direct short (zero ohms, or close to it) or an open circuit (infinite or very high ohms). Edit: I should clarify this resistance test can NOT conclusively prove the pump is good. It's more of a test to weed out one that is blatantly bad.

The next step is something I haven't covered before, but it's a quick and dirty test of the pump. You've got to promise me you will do it EXACTLY as I will describe for maximum safety. Please run through the previous steps 1-4 first, just to check power, inertia switch good, etc. You had already swapped the fuel pump relay R7 with the one for the fog lamps, so we know that relay is good, too.

Leave the connector disconnected after the resistance checks you just did. We're going to skip the rest of the pump control circuit and momentarily apply 12VDC directly to the pump connector and see if the pump runs. But don't just rig up a pair of jumpers and start throwing power around. It's VERY important to have a fuse in your test circuit. We're going to use an existing fuse that feeds that pesky relay R7.

Pick up a set of test jumpers with alligator clips at each end. At the fuel pump connector, pick one of the wires and connect it with a jumper to a good ground. I don't know if the pump is polarity sensitive (many are not), so just pick one wire to try as ground. If that doesn't work, we can swap leads later and try again, but don't worry about that for now.

For the other pump wire, you will need to run a LONG test jumper back to the rear power distribution box in the trunk. You can fabricate a simple jumper by adding small alligator clips to a long piece of wire. Or if you have a pair of premade jumpers with clips at each end, you can put a long stretch of plain wire between the two and end up with the equivalent of one long jumper. Wrap tape around the clips in the middle so they don't accidentally short to ground.

With your new long jumper, connect one end to the remaining wire going to the fuel pump. At the far end, back in the trunk, remove relay R7. Unfold a paper clip or fabricate something similar to reach into socket #3 for relay R7. This is unswitched battery power, protected by fuse F17 in the rear power distribution box.

When you make contact back there, the pump should run. With the engine off and the rear seat's bottom cushion removed, you should hear it. Only let it run for a few seconds and then disconnect the power. Go up front and check the Shraeder valve. If the pump is good and filter wasn't clogged, you should have pressure. That tells us the pump will run and the problem is on the control side.

If you don't hear the pump run, double check for power at that relay socket. Make sure the ground jumper connected at the pump is making a good connection, too. If all good, swap the two test jumpers at the pump connector to reverse the polarity and try again. If you try the polarity both ways and the pump still doesn't run, your $10 pump was no bargain...

This is VERY important: Always make or break the test connection back at the trunk. That way, in case there's a spark, it is well away from any potential fumes near the fuel pump."

 

You will most likely need a helper as the electrical current is send to the pump when the ignition is activated and then terminated once a preset fuel pressure threshold is achieved. If the fuel system does not pressurize, I would expect that there is logic in the ECU that times out the fuel pump in case of a leak...

This is not Jag specific, but I am tossing the idea out there as food for thought...

 

Excellent point. I think the initial start-up logic is based on a timer, not fuel pressure, but am not really sure. Whatever it is, I didn't really go into that in my recent treatise, but in post #24 above, I gave one method to test the pump that gets around this potential limitation.

 

I jumped the gun and did something else out of curiosity and we all know what curiosity does. Well I took a foolish chance, was as careful as could be and got some results. I'll go backwards and try some of your other suggestion too but I first wanted you to see this:
I pulled the entire pump mechanism back out of the tank. I then took the perfect size Tupperware lid and tapped it super good to the hole of the tank. Then I took another Tupperware lid and tapped it to the top hole so the only thing poking out was the pigtail wire connector.
Before I turned on the key I took the fuel pump mechanism into my shop. I very carefully pulled back and cut out the black shrink wrap to expose the wires and the colors of the wires. I then made the very slightest slice in the covering so I could apply 12 volts from a 2 amp battery charger. Right away the first two wires that I suspected fed the pump, the pump started up. Now I know that the connection right at the pump is good. Then I went back to the car, turned on the key and put my meter back in the same two sockets. So for now it looks like the motor will indeed run when and if it's getting 12 volts.
I also removed the plastic mesh filter and blew through in in both directions. It does not appear to be clogged. Now, back to putting it all back in the car and proceeding to your other instructions. Thank you for listening to the adventurous and sometimes foolish side of me.






Red wire w/ black stripe has tiny slit for testing. Black wire also. These match up with the sockets on the upper left and lower left
Upper left socket is R/B and the lower left socket is Black

 

Yes, I know, it was (maybe) dangerous but I took a long time to seal off the gas tank. I'm done with all that now. It seems as though the pump does indeed work and the filter is not clogged so I'm going to put everything back in the tank and reconnect the elec. and the fuel lines. By the way, there was not a black wire with a red stripe or a green wire with and orange strip. the colors going into the pump were solid black, solid red, red w/ black stripe and yellow w/ white stripe. Is there any reason I shouldn't put everything back in the tank. By the way, I read your warning AFTER I did this test. Ooops... I'm still here.

 

 

 

Or this:

 

The first Tupperware lid fit VERY well over the hole in the fuel tank itself but I tapped it down anyway. Being overly cautious I put a second lid over the hole in the floorboard and tapped it VERY well around the female end of the 4 wire connector, just to make sure I couldn't smell gas any more. I felt confident that this was safe and I'm still here talking about it. It was a quick check with the key on and with it off. I discovered that I did indeed have 12 volts coming from that connector.
Yes, I only replaced the motor itself. A female, two wire connector plugged into the new motor. I wasn't 100% sure that voltage was reaching the motor from the connector outside the unit so in my bench test I made a super tiny slit on the two wired I deemed had the 12 volts coming from the car. I was right on the first try. Using a 2 amp charger, I simply tapped the bare wire briefly and found the the motor ran. Had the pigtail on the outside of the unit been a female connection I could have touched the voltage there. I didn't see a way to touch those tiny little male pins. So my conclusion on this test was, the motor works with the connection in the device and there's 12 volts coming from the car side. Yes, indeed, you are absolutely correct about the load. I'm pretty darn sure the wires were not crossed in the process. I did not "backfeed" any voltage because the entire unit was out of the car.
My next test if to do what you suggested with the long wire. After that, I don't know.
Question: will the pump refuse to start if there is any kind of an air leak along the way? I (think) I understand that an air leak might keep the fuel rail from pressurizing but would the pump spin anyway?
Am I possibly looking at a worst case scenario on having a bad RECM? I'm not quite clear on how to test that. I'm pretty darn sure I've tested all the relays and fuses.
Thanks for all you help. I'm painting a target on my back and shipping you more darts.
Have an incredible day.

 

I do! With the pump installed in the tank and with the two lines connected, I want to see if the pump builds up pressure under load using fused battery power, bypassing the input controls. If so, then we've got an input problem and the pump is not receiving the proper signal to run. If the pump motor runs but there's no pressure, then we've got a mechanical problem (bad pump, etc.) or a plumbing problem (blocked tube, etc.)


With any leak in the lines, the pump should still run. If the leak is on the intake side, the pump will suck in air instead of fuel. If the leak is on the output side, pressurized fuel will spray out.

 

Steve,

Any progress? Please see post #7 in this similar thread, for a long-winded treatise on today's theory of when and how the pump is energized:

https://www.jaguarforums.com/forum/s...0/#post1871850

Specifically, please see my comments about the power supply to the pump via the RECM. I think when the ignition is on, the pump gets a constant 12v input to one wire. However, the pump only runs when the RECM also supplies the ground to the other wire. If my thinking is correct, it's normal to see 12v at the one wire, but the important thing is you also need the ground (supplied via the RECM) to complete the circuit. The ground probably modulates to control the pump speed, too, so it would be tricky to verify with a simple meter measurement.

So even though the pump control details may be different than I was previously thinking, the test I have in mind is still the same.

 

It's PWM I think you'll find - see section 10 of the workshop manual (JTIS).

 

Okay, I'm back at it here on Saturday afternoon. I did indeed find the green wire with and orange stripe on the "car side" of the fuel pump wiring harness at the connector. But I also found two black wires with a red stripe. Now, with the relays I can see the almost impossible to read little numbers that ID the wire. I can not see any numbers on this fuel wiring harness at the connector. Obviously I can transfer the GO wire to the pump side of the connector but which BR wire do I choose? Also, do I strip back some with once I identify those wire so I can put an alligator clip on it? And yes, I get the part about putting tape on the alligator clips to prevent shorting.
On this same tread, once again, I'm finding myself lost in trying to read and locate certain issues on the PDF shop manual I have now. I was directed to go to ebay or Amazon to find one. The ones I saw in there look like someone printed out the one I already see on my computer screen. I was looking today for a diagram of that fuel pump connector to ID those BR wires.
Also, I apologize if I've jumped off the thread where you gave all these instructions on testing the electrical from the relay socket to the 'unplugged' fuel pump. I couldn't find that thread again.
Thanks again for keeping me from having to do housework instead... (grin)

 

SUCCESS ! ! ... Sort of.... darn, I got all excited there for a minute. When I used the LONG jumper wire from the #7 relay in the trunk, socket #3 to the GO wire on the unplugged side of the fuel pump and a ground wire from the BR wire at the fuel pump to ground, I got plenty of pressure at the fuel rail. So I put the relay back in, plugged the fuel pump harness back together and still no starting. Now what? Is it electrical? Remember, I did't get pressure before. Should I release all the pressure in there now and they try to get it back by turning the key? Makes sense, but I have a funny feeling I won't get pressure that way. Could this in fact be a bad RECM? Is there a test for that? Moving right along in the key of life.

 

Progress! Now some more squirrels are going to come hopping along and entice you, with their big bushy tails. No chasing them. Stick to the plan.





Is the problem electrical? Define "electrical". All we know so far is your fuel pump apparently wouldn't run until we fed it power/ground directly, bypassing most of the control circuit. We do know the problem isn't mechanical, such as a clogged filter, totally dead pump, etc., but that's all we've learned so far. Baby steps, and do NOT read too much into each one...

Electrical? The root cause could be just that, such as a loose socket where relay R7 plugs in. Or all the wiring could be fine, and there is some unknown reason why the fuel pump operation is purposely inhibited. For example, is that normal operation if the antitheft system is triggered? That's a big IF, and I really don't know. I mention all these possibilities not to scare or distract you, but to help concentrate on what we do know, and not to overlook or be misled by other possibilities.


You can try this if you'd like. As previously mentioned somewhere in the World-O-Steve and your many threads, I don't know the exact details of the pre-start priming logic. In fact, I don't need to know them. All I do know is under normal circumstances, the pump only runs briefly before engine start, to prime the injector rail. Whether the pump shuts off via a timer or in response to the pressure sensor? Good question. I don't have an answer.

Just curious, when you did have pressure in the lines, did the engine have any different response with the starter engaged? With zero fuel pressure, there was nothing at all to ignite, so no combustion. I'm wondering if the primed injectors sprayed just enough fuel for the engine to at least cough once or twice.



I do not know of a test at our level for the RECM. The dealer-level diagnostics can probably view all of the inputs, and then command the outputs and see how they respond. The only way I know to test it without such equipment? It is by process of elimination, circumstantial at best. You can make sure all of the inputs are valid. Then you can make sure all of the outputs respond properly. We are definitely NOT there yet. All we've really done is make sure a single output (pump on) responds properly, but even then, we haven't tested the complete wiring in between.

As JagV8 has already replied in that other thread, the RECM is NOT plug and play. Ooh, but there's a fresh S-Type in the wrecking yard, and I bet I could just try that module and see what happens... No, please don't. Some of the modules have VIN-specific software loaded in them, and the modules communicate this data with each other. If the disagreement is bad enough, the modules may, for lack of a better term, go into a protective shutdown. If that happens, it won't be a simple matter of reinstalling the original module and expecting all to return to normal. I know you're itching to get this fixed, but swapping used modules can be a real can of worms that often requires reloading software.

If we rule out all other possibilities, and it does like your RECM is the culprit, you'll probably need to take the car to the dealer or a Jag specialist who has the proper capabilities. But remember, we are NOT there yet. Don't panic and make things worse.


What I'd like you to do next? Continue checking stuff. Remember, we haven't gotten very far yet. It seems that instead of actual troubleshooting, I've spent more time talking you down from the ledge and getting you to stop chasing squirrels. How about we get you a dog? Turn him loose to chase those pesky squirrels and you can concentrate on fixing the poor car.

Let's look at relay R7 some more, back in the trunk. You've swapped it with a known-good relay for the fog lights. The fog lights worked before and after the swap, right? That should prove you've got a known-good relay for the fuel pump, but let's take it further:

1) Have a helper turn the ignition from off to on and then back off. You stand in back with your calibrated finger on relay R7. When the ignition is switched on, you should feel the relay click. When the ignition is switched back off, you should feel another click. Usually the click on is stronger (pulled by the internal electromagnet) than the click off (pulled by a spring), so don't let that throw you. For comparison, go to the front and feel the click for that same type of relay as the fog lights are cycled on and off. A proper clicking action tells us relay R7 has a good 12v control signal to socket #1, and a good ground at socket #2.

2) Take relay R7 with you to your local hobby shop or hardware store. Look for the display of little brass strips and tubing from these guys:

Retail Merchandisers - K & S Precision Metals: Full Line Metal Specialists


Find a brass strip with the same dimensions as the tabs on the relay. Use the brass strip as a go/no-go gauge to make sure the sockets will grip the relay tabs properly. If only one socket was loose, you'd never realize it when installing or removing the relay. But if you test them individually with a brass strip of the same dimensions, it will be obvious if a socket is loose.

3) Let's test the internal contacts of the relay. In theory, swapping a known-good relay from the fog lights should have been adequate, but the pump may draw more current and thus aggravate a marginal connection, so let's test a little deeper to be sure.

Set your meter to ohms and select the lowest scale. Touch your leads together and note the reading. This is the resistance of the leads themselves. The reading should be very low, only a fraction of an ohm. Now connect the leads to relay tabs #3 and #5. With the relay deenergized, there should be no continuity. Leave the meter leads connected to the relay.

Next we will use the battery to energize the relay. Connect one test lead from tab #2 to the battery's (-) post. Connect another test lead from tab #1 to the battery's (+) post. The relay should click as the electromagnet is energized. The ohmmeter should now show good continuity, only a teensy bit above the previous reading you took with the two meter leads touching. That tells us the internal contacts are closing properly and making a good connection.

 

One more thought for you. This would be the next step after the electrical checks in my previous reply.

Connect a mechanical pressure gauge to verify the pump output is within specs. Previously you had zero pressure, but after jumpering power and ground to the pump, you had some. How much? For all we know, it could be only a fraction of what is required, so the engine still won't run and you're left scratching your head...

 

Still waiting to hear if there is spark... all this time spent and no-one checked it. The no-pressure-no-spark-combo is kind of important here.