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The fuel pump on my 2003 Jaguar Xtype 2: Ltr. Had a broken wire but after I reconnected it & refitted the pump, there seems to be NO power going to the pump.??
Docko: Check for voltage to the fuel pump during the first ~5 seconds after you turn the ignition key from the off position to the run position (not the start position). The fuel pump should energize for ~5 seconds, then power down each time you turn the key from off to run. If it doesn't, check the voltage to and from the fuel pump control module, again during the ~5 seconds after you turn the key from off to run. It's under the rear seat cushion on the left hand side / US driver side.
The fuel pump and relay for your 2.0L is on pages 53 & 54, Fig. 03.4
For the fuel pump relay, next to the battery in the "Power Distribution Fuse Box":
+ Contact #5 / Green wire w/ Orange Stripe should have ~12V when the relay is switched closed, i.e., with the ignition switch in the run (II) or start (III) positions and the ECM connecting Contact #2 / the Green & Red wire to ground.
+ Contact #3 / Orange wire w/ Green Stripe should have ~12V direct from the battery
+ Contact #1 / Brown wire w/ Green Stripe should have ~12V when the ignition key is in the run (II) and start (III) positions
+ Contact #2 / Green wire w/ Red Stripe goes to pin EN65-099 in the ECM. This wire is normally disconnected from ground when the ignition key is off, and switched to ground when the ignition key is in the run (II) and start (III) positions. Test this wire for very high resistance to ground with the key off, and very low resistance to ground with the key in the run (II) position.
If you find ~12V in the Green & Orange wire at the fuel pump relay and 0V in this same Green & Orange wire at the fuel pump, look for a break in this wire. It helps to have a wire tracer, which sends a signal tone down the wire for you to trace until it stops at the break. Here's one example: https://www.harborfreight.com/cable-tracker-94181.html
Thank you, dwclapp. I have looked at the wiring diagram you kindly posted, but honestly, I might as well be looking for a needle in the proverbial haystack. However, I will find an Auto Electrician & hopefully he can work it out. You say there’s a RELAY on this model, (2 ltr petrol v6 engine) & that it’s located next to the battery, so I’ll check that out & maybe find a broken or disconnected wire. I shall keep you posted. 👍
Docko: Before you hire an electrician, try this.....
Under the hood, next to the battery, is a black plastic box called the Power Distribution Fuse Box. The exact location in your X-Type is shown on page 18 of the wiring diagrams I sent you earlier (page 20 of the pdf). Open the lid and inside you'll see several fuses and relays that look like page 16 in the wiring diagrams (page 18 in the pdf).
Find relay R11 - the relay for your fuel pump. It's probably identical to the horn relay R3, the windshield power washer pump relay R4, and the A/C compressor clutch relay R6.
Swap the fuel pump relay with one of these identical relays. If the fuel pump starts working and the other system stops working, then you confirmed the fuel pump relay was the culprit. Buy a replacement relay with the matching part number. They sell here for $15-20 and are usually stocked by auto parts stores because they fail with age and usage.
Thank you so much dwclapp, I followed your instructions & swapped the fuel pump relay for the horn relay, but regrettably, the pump still failed to operate while the horn worked fine with the transferred relay. I assume then that it’s not the relay. However, please try to come up with another idea as I’m open to anything, at this point. It has me totally stuffed. If you think I should buy another relay & try it, I shall do so ?
Docko: In a related post you said the fuel pump works when you 'hot wired' it with 12V directly from the battery, you've checked the inertia switch, and tried swapping the horn and fuel pump relays without success. Buying a replacement relay won't work, for the same reason swapping relays didn't.
Can you buy or borrow a multimeter to do some simple tests?
Under the back seat, unplug the electrical connector for the wires to the fuel pump. Also, remove the fuel pump relay from the fuse box and look for the 4 small electrical outlets that the fuel pump relay plugs into.
Set the multimeter to ~20V DC (might be a V with a straight line, not a V with a curved line). Connect the black multimeter wire to the NEGATIVE battery post or any bare metal on the car. With the red multimeter wire, test the voltage of all 4 small electrical outlets under the fuel pump relay:
+ With the ignition key off, one outlet will have ~12V all the time. That's #3 in the attached diagram. It supplies power from the battery, thru the relay, to the fuel pump.
+ Another outlet will have 0V when the ignition key is off and ~12V when the key is in the run (II) and start (III) positions. That's #1 in the attached diagram. It switches the fuel pump relay from off (open circuit) to on (closed circuit) when you get in the car and turn the ignition key from off to run (II) or start (III).
+ The remaining 2 outlets will have 0V all the time while the relay is removed.
To identify the remaining two outlets, set the multimeter to read resistance, say ~100 or 200 ohms (Ω symbol). Again, connect the black multimeter wire to the NEGATIVE battery post or any bare metal on the car. With the red multimeter wire, test the resistance of the 2 remaining electrical outlets for the fuel pump relay. Do NOT do this test on outlet #3:
+ When you turn the ignition key in the run (II) position, one outlet with have very low resistance, perhaps 1Ω or less. Turn the ignition key off, and this resistance will become so high it's off the scale. This is outlet #2 in the attached diagram. It's the ground connection for the fuel pump relay. When the ignition key is in the run (II) or start (III) positions, this connection becomes a closed circuit to ground so the fuel pump relay can do its job off supplying power to the fuel pump. After an accident, the inertia switch can reopen this circuit to cut power to the fuel pump, but you already confirmed the inertia switch button is closed.
+ The remaining outlet is #5 - the power supply to the fuel pump. It will have a high / off the scale resistance all the time, whether the ignition key is on AND off, because you temporarily disconnected the fuel pump wires at the back-seat.
+ Now re-connect the back seat electrical connector to the fuel pump, and recheck the resistance between outlet #5 and the negative battery terminal. The resistance should be much lower, perhaps 2-10Ω's, instead of high / off the scale resistance when the fuel pump wires were disconnected. If the resistance remains high / off the scale when the back seat wires are plugged into the fuel pump, then there is a break somewhere in the Green / Orange wire between outlet #5 in the fuse box and the back seat electrical connector. To find this break, it would help to have a wire tracer. We know the break is not inside the fuel pump because you confirmed it works using a 'hot wire' from the battery.
Let me know what you find and I'll walk you thru the next steps.
07-31-2018, 09:39 AM
