Combination of Issues
 

I have a combination of issues on a 98 XK8 - I am leaning that it must be a control module or electrical issue, or just random items hitting all at once...

Have been having a ASC light come on about every third or fourth trip out. Clears when car is restarted, no noticeable other symptoms. Shortly after this started (months) she throws the Lean codes just after the tank is filled up. These don't display after restart either. More recently, when Sport Mode was enabled, she threw the gearbox fault light and went into limp mode. Reverse pulls, only forward in 4th, each light on the shifter lights up when in that gear..

My HF scantool used to pull and clear the P codes.. Now it fails to connect to the vehicle. Was hoping for a bit of experiential input before I go down the Electrical Rabbit Hole. I have way more experience with Spitfires and MGBs - so steer me in a good direction.

Couple of other things - Battery was 5 years old - have a new one in now but same issues. AC had the code 20, but pressure switch is in, and code has not came back. (no cold air yet, still need to verify Compressor clutch is engaging...)

Thoughts fellow enthusiasts?

(I'll get the profile updated!)

Welcome techiki, we hope you enjoy your time here and find answers to your issues. But first, we would appreciate it if you'd introduce yourself here (site requirement)....https://www.jaguarforums.com/forum/n...-intro-must-5/

For your issues, we need those codes to give some direction. If you have those ones you cleared, please post them. If your scan device has failed, any national auto parts store can scan if for you...it OBD II. I can guess your ASC issue is a standard one of the solder joints just needing redone, but without the codes its a blind method. For the lean codes, those could be a number of things, again we need the codes.

We also need your vehicle year and model, example...XJ and XJR came with different transmissions and other components over different years. You can list it in your signature which will save posting it all the time.

We look forward to your information.

Thanks -- Intro added!

Looks like I started this in the wrong area - perhaps a mod can move it over to the X100 area...

I just received the ICarSoft Scan Tool yesterday. Pulled following codes: P1797, P0732, P0733, P1722, P0790 and C1155 from the ABS Module. Checked the Capacitors in the ECU - no leakage. Scantool connects intermittantly to the ECU, but can see the ABS and TCM. Codes were cleared out, car shut off, and then checked again. Reverse works fine, but Drive has the same rev to 1500, cluck, and fail safe 4th gear.

Disconnected the wheel sensors, and both fronts read as closed circuits testing from the connection to the sensor in the engine bay. Pins 14 and 42 read 1600-1800 and 16 and 44 read 1650-2100 on the TCM connector. Wheel sensors and harnesses for both fronts are on the way. Looks like It'll be pulling the trans pan next - to see if there is any shrapnel...

Hi techiki,

Welcome to the Jaguar Forums! It's great to have you with us.

Here are a few documents that will be helpful:

Jaguar X100 DTC Summaries 1998

ZF 5HP24 Transmission DTC Summaries 1998

Jaguar X100 Electrical Guide 1998

Jaguar X100 ABS-TC DTC Summaries 1998

Just a quick review of the possible causes of some of your DTCs suggests a few things you can do for starters:

1. Check the transmission fluid level and correct if necessary. Use only a proper fluid. Do not be fooled by Valvoline and other brands that claim to be "suitable for use" in your transmission or "meets ESSO LT71141 standard." The fluids below are known to be correct. The best deal I have found in the U.S. is on the Febi, which is offered by several eBay sellers. Just be certain to buy the correct part number because Febi also makes other transmission fluids:

ZF LifeGuard 5
ESSO LT 71141
Febi Automatikgetriebeöl Nr. 29738
VW/Audi G 052 162 A2
Pentosin ATF 1
Ravenol ATF 4/5 HP

2. Disconnect and clean the transmission electrical connector with zero-residue electronic cleaner, allow to dry, then reconnect;

3. Clean the front left ABS wheel speed sensor because metallic brake dust rotor rust particles are attracted to the sensor's magnetic field and affect the sensor's signal. Also, check the sensor's electrical harness for a break by connecting your ohmmeter to the sensor leads at the ABS Control Module connector and manipulating/flexing the sensor's wiring harness along its length between the sensor and the point where it goes into the body trim. Off the top of my head, your resistance readings were in the ballpark, but broken wires in the harnesses are a common cause of intermittent open circuits. Here's a document that shows the pin breakout at the large ABS Control Module electrical connector, courtesy of our member Gus:

Jaguar X100 X308 ABS Hard Fault Check Sheet

Cheers,

Don

Thanks Don,

I have the ATF ordered, (Esso) and have a replacement wheel speed sensor in hand. Wrong harness was sent - figured I'd grab one just in case since it sounds like that's a fairly common issue and not a bad thing to have on hand..

After clearing codes, it backs out of driveway fine, but immediately went limp mode switching in to Drive. By Immediately, it felt no pull till about 1200 rpm when it cluncked into fourth, threw the warning and slowly pulled back into the driveway. Scan tool was unable to link to ECU or TCM. Pulled battery, unhooked the TCM and left overnight. Put freshly charged battery in (it read 12.84v and one pulled read 12.5v) and was able to link and pull codes. With car idling, pulled out a P1722, P0790 and a battery fault code (first time for that code) these codes came from the TCM, ECU read no codes.

ABS was clear of codes. Funny thing was while watching live data, the scan tool lost connection to the ECU and TCM and wouldn't link back up to them. I'm feeling like there has to be an electrical issue not mechanical - but we'll see...

Does the TCM need reflashed if a used one with same VCAT# is used?

--
Dusty

Hi Dusty,

Electrical issues are more common than mechanical ones, though there are a few well-known mechanical failures too. Failure of the TCM is relatively rare.

Regarding your DTCs, did you check the transmission fluid level and clean the transmission electrical connector? While you're under there, also check that the screws that secure the gear selector cable bracket are present and tight. The most likely cause of your transmission codes is oil contamination of the electrical connector.

Beyond that, since your scan tool is having trouble communicating with the ECM and TCM, it might be worth checking the Electrical Guide for the locations of the ground points referenced by the ECM and TCM and cleaning those points by removing the nut and harness eyelet connectors from the threaded studs, cleaning all the parts with a brass-bristle brush and zero-residue electronic cleaner spray (never use sandpaper), allow to dry and reassemble.

It would also be worth locating connectors related to the CAN bus and disconnecting all you can access and flush them with electronic cleaner, allow to dry and reconnect. These include the connectors at the ECM and TCM, but other connectors are shown on the Multiplex Systems/Networks diagram near the end of the Electrical Guide.

Cheers,

Don

Haven't crawled under yet - Temp here has been in the 90s, supposed to be cooler next few days. I have the ATF and a filter/gasket arriving tomorrow, so plan is to swap the wheel speed sensor tonight and to check the harness on the front left. Will also be looking at the AC clutch wiring and pressure sensor (I replaced the sensor to clear a 20 code on the AC but now it blows the 10A fuse for the AC Clutch when AC is turned on) She should be up on stands tonight prepped for the under car work.

I'll check the linkage cable and connectors on the Trans tonight, probably wait for fluid check tomorrow when fluid arrives. Have the service items ready, it's about 50K since last service on the transmission so figured if I need to look, I may as well get that done now too..

Plan is to check fluid before service. I'd like to have the electrical ruled out before I service it - if it's mechanical it'll be getting a rebuilt Transmission anyway.

Thanks again for the assist - really appreciate the steering me in the best direction!

--
Dusty

Hi Dusty,

In case you don't have the fill procedure for the 5HP24, attached is a TSB with the revised procedure. To monitor the transmission fluid temperature, it's most convenient to do it via IDS/SDD or a scan tool that can display Live Data. Otherwise a no-contact infrared thermometer will work as long as you use it to measure the temp of the fluid draining from the fill hole and not the pan, since the pan temperature can differ from that of the fluid by several degrees.

Cheers,

Don

Thanks for that Don,

Work's been in the way so far this week, but gotta rake that hay while the sun shines as they say!

I did crawl under tonight and take a quick look underneath. I'm guessing the Trans electrical connector is at the rear of the trans toward left side. I noticed that the wire colors are visible for about a 6" length before entering the loom jacket, not sure that's normal? Cleaner arrives with the fluid and filter kit tomorrow, so I didn't pull the connector out yet. Looks like the shit cable is connected without any slop too. Can't say that it's in proper position - will need to check that.

I did hook the scan tool up, and it saw the TCM and pulled the same 1722 and 0790 codes. Cleared them, restarted, and showed codes clear for a minute or so, then they came back without any movement of the shifter. No Gearbox fault warning or MIL lit though, so I'm guessing the codes weren't actually cleared. As I understand the 0790 on the mode selector defaults to normal mode if there is an issue with the sport switch. The 1722 I'm more uncertain on the circumstance, but guess that when Drive is engaged, and revs are high but wheel speed is low it throws limp mode.

What's odd is that none of my three scan tools see the ECM. Unless I pull the battery, and hard reset after 30 mins or so. When it does link to the ECM, there are no codes. Even stranger is that all this limp mode issue started the same day I swapped out the AC Pressure Switch.. Beginning to think that with the way the electrical system seems to be so temperamental that I may need to check that connector and see what happens. Just find it REALLY hard to believe that something in the AC system would cause an issue with the TCM....

Looks like I'll be buying beer, bringing the crew over this weekend and running through it all. Still more excited to troubleshoot this Jag than the Miatas!

--
Dusty

OK - had a chance to drop the pan off the transmission. Figured that since it was close to needing to be serviced and I'd be under the car already, might as well get it handled.. Found a fair amount of dust, and a few larger shavings. Looks like I'll get a rebuilt transmission coming...

https://cimg1.ibsrv.net/gimg/www.jag...8a544c25e6.jpg
https://cimg4.ibsrv.net/gimg/www.jag...0091b90752.jpg
https://cimg6.ibsrv.net/gimg/www.jag...09fc557b43.jpg

Yep, there's definitely a problem. I'm going to PM Bob Gauff (motorcarman) to see if he has an opinion on your photos and whether he thinks an A-drum job will be enough or whether they'll have to go deeper.

Cheers,

Don

motorcarman was kind enough to reply to my PM and rather than posting here he just gave me his thoughts, which I'm reposting here:


That is a lot of steel debris but I don't see CHUNKS so that is good.

Sounds like a failed forward drum so that is where I would start.

Losing the ECM on the CAN bus is not good. Could be a network fault or a module fault?

All the P07xx or P17xx faults need to be addressed. No idea why the ECM would drop off the network like that.

I would like to use datalogger and sit in the passenger seat to watch the ECM,TCM and ABS.
The selector lever illumination module is on the CAN bus but is a 'listen only' node. It can interrupt communication but usually not a likely cause.

Sometimes swapping modules can pinpoint a problem but without WDS, IDS or PDU the ECM cannot be configured for immobilization setup from the 1998MY onward.

These modules are now becoming DECADES old so unfortunately electronic problems will be more prevalent in years to come.

bob



__________________
Owning and repairing British and German cars since the early 70's

1999 VDP Topaz Parts or Project??
2001 XJ8 Mistral
2000 XJ8 Platinum (project)
1999 XJ8L Topaz
1985 XJ6 Belgian Import (Gray Market project car)
1985 XJ6 (Parts Car)
1983 XJ6 (Parts Car)
1992 Sovereign (sold)
2001 S-Type 4.0 (sold)
1997 XJ6L Black (sold)
1997 XJ6L White (sold)
1972 XJ6 (sold)
1966 'E'Type (first Jaguar) (sold)

Thanks Don - and thanks to you too motorcarman!

Either way, it looks like the transmission is coming out. Won't be able to pull it for a week or two - my son's Spitfire is in the way, but we should have the body off the frame in the next week and those will go off to media blaster..

I'll get it in the garage and pulled out and we'll see how bad the Drum is. I'm probably going to grab a rebuilt unit regardless, never a bad idea to have two working transmission... I'll add them to the 5 or 6 power trains in my garage at the moment. The ECU issue i'd like to work out though. Is it possible to disconnect all other modules but the ECU and have it respond key on, engine off? That might help with troubleshooting that module.. It is clean, no obvious issues with solder joints, etc. I'm thinking it's hanging communication talking to a module it doesn't like, but I base that on my computer background. It can be seen if a hard reset is done, but then loses connection a few mins in. I'll go digging for the wiring diagram too - might be good to test all the wiring runs while it's down. I thought I saw one around here somewhere, but didn't bookmark it..

--
Dusty

Definitely think something is up on the CAN..

Repaired ABS module came today. I tried to pull codes from ECM and ABS modules before doing anything. No link to scantool. TCM would link up with the same two codes, but would fail trying to clear.

Disconnected battery, and unplugged ABS Module. Connected the battery, and was able to look at data in the ECM and was able to clear TCM codes. ECM threw a failure to connect to ABS Module code.

Disconnected battery, and swapped ABS Modules. Reconnected battery, and can't link to ECM, ABS or TCM.

I have a second TCM that I'll swap out next. Have another ECM en route, but will require flashing to get it to work. Thinking I should try following:

1 - try to pull ecm and tcm codes with ABS module disconnected.
2. try to pull ecm and ABS codes with TCM disconnected
3. swap in second TCM and try to pull ECM ABS and TCM codes

Any other modules on the CAN besides the ECM, TCM, and ABS?

Hi Dusty,

The components and harness connectors on the CAN are shown on pdf page 70 of the Electrical Guide I provided the link for in post #4. I would recommend that you disconnect every CAN connector you can access, flush with zero-residue electronic cleaner spray, allow to dry and reconnect. Also inspect the connectors and wiring for any visible damage. The CAN wires are easy to identify because they are pairs of Yellow and Green wires.

Also, beginning on pdf page 118 of the Electrical Guide is a list of CAN Messages by Node.

Cheers,

Don

Cleaned connectors on the TCM, ECM, ABS, and JGate. Connected battery, and have connected to ECM, TCM, and ABS modules with no issue a few times now. ABS code throws P1676. Will be looking at fuses again, battery charge, and power to ABS Module next. Car is parked on slight incline, does not feel like Drive will hold the car without rolling back. No code from TCM yet, but only at idle shifting through gears to make sure JGate illumination still works.

Will double check the resistance on the wheel speed sensors at the ABS Module Plug, look at the AC clutch blowing fuses issue, and clean all transmission connectors next. Then I'll test all buttons in the car, check if any new codes, and if all clear, see if transmission still has issue. If it throws the 1722 code, I'll pull the trans and check the A Drum, and valves..

Will update this weekend as I dig in further!

Been travelling a bunch for work, so just got the chance to dig into the transmission...

We have an A Drum failure!

https://cimg7.ibsrv.net/gimg/www.jag...b0a68e7169.jpg

Yet another ZF5HP24 A Drum failure
 

Sorry to hear about your transmission problem. Yet another in a long list of A Drum failures. A common weakness of the ZF5HP24.

What’s your plan of attack now? Reconditioned unit? At least make sure you’re replacing with the up-rated A Drum and the upgraded PR valve. If you can, I would also check the valve body solenoids too and the F clutch.

Anyway, you obviously know what you’re doing, so good luck and keep us informed of what you decide.

Well, plan is a bit of both..

I am picking up another unit to have on hand for the next time. I have the heavy duty A drum and upgraded PR valve already, but just ordered an overhaul kit, the needle bearings, pistons, etc. to give the original unit a going through. She's on the project list now with the Rambler Wagon, the Spitfire, and the Metropolitan race car.

She needs an AC compressor too, so that's on the list. Current goal is to have everything sorted and working by end of the year.

Back with more soon!

Little break from with with the holidays = transmission should be back in the XK8 this week! Bell housing is back on, just waiting on the Transpo PR to freeze tonight and then bottom will be buttoned up. Should have the fluid pre-fill done tomorrow and the trans back on the transmission jack.

Was hoping to install using the Max Jack 6 I ordered in October, but they're still back-ordered so looks like it'll be done on jack stands.. Hoping I don't have to fight the cat converters too much...