Gentlemen,

Hope some of you Td5 Jedi masters will be able to end my agony.
I’ve a pretty well rebuilt 2004 110 SW Defender (LHD). Started with a galvanized and powder coated chassis, everything bar the engine fully rebuild or new, but now after just over a year most of the parts back on it won’t start

Turning the key into position ll lights up a red OIL light and a red BATTERY light only!
No fuel pump sound! (New and confirmed working by forcing its relay to close manually). The engine is cranking but won’t fire up


Things that might matter:

- New DENSO starter, new DENSO alternator, new VDO fuel pump + lines, new VDO MAS sensor, new injector harness

- temperature gauge reading normal

- No central locking

- No power in the OBD port

- Fuses all checked

- Relays appear to be working as they should* (when tested with 12V directly from the battery)

- battery voltage 12,4V

- Immobilizer + fob present - I don’t get the red or red flashing light in the speedometer: when arming the immobilizer with the fob the dash indicates by both indicators flashing 3 times (when I try to start then - both indicators keep flashing on the dash for few seconds along with the CHECK ENGINE light that stays on constantly and can’t even crank the engine), when disarming both indicators flash 1x on the dash (when I attempt to start, the engine cranks but doesn’t start, no fuel pump sound…

Please help

check you have voltage on under seat fuse box on C0622-1 and C0623-1 and that link 1 is ok and all earth header are attached

Last time I had these symptoms, it turned out to be an ECU failure. You mention the OBD port, so I'm guessing you've plugged a diagnostic device in. Is there any communication with the ECU at all? If so, are there any faults recorded?

ignore previous as you have power via ignition switch oil and charge lamps .have you checked you have power from under seat box fuse 4 fuel pump and power on fuses 8 to 17 and fuses 28 to 36 all fed from ignition switch
have you checked that all the relevant earths are attached and that the headers are all in good condition

Corris110SW said:

when I attempt to start, the engine cranks but doesn’t start, no fuel pump sound

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I would occasionally have this problem with my TD5 and it was the fuel pump relay. Despite working when bench tested and having food connections (removed the pins and tightened the spades) it would still fail and a wiggle of the relay would rectify the issue. The relays are prone to internal failure and movement, something I picked up form @Brown. I currently have the same problem with my starer relay on my 110 (300tdi wiring). If you have confirmed you have power as above, then I would consider replacing the relay as a quick check before digging further into the wiring.

Yes, about ten years ago I discovered that I could change the engine note of my TD5 by wobbling the fuel pump relay, which seemed a little worrying. Interestingly, once started, a TD5 will run without power to the fuel pump, just not very fast.

Brown said:

Last time I had these symptoms, it turned out to be an ECU failure. You mention the OBD port, so I'm guessing you've plugged a diagnostic device in. Is there any communication with the ECU at all? If so, are there any faults recorded?

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No communication at all.. Just prob with the AS10 immobilizer unit as I was able to get the EKA code from it…

mystery said:

ignore previous as you have power via ignition switch oil and charge lamps .have you checked you have power from under seat box fuse 4 fuel pump and power on fuses 8 to 17 and fuses 28 to 36 all fed from ignition switch
have you checked that all the relevant earths are attached and that the headers are all in good condition

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All fuses checked - display battery voltage on both sides of the fuse. Checked the earth wiring. Appears to be good, have constant negative in Black ECU Plug on terminals 1, 2, 24, 25. Headers seem to be fine, are they prone to failure? Is there any particular one to do a “proper” check on?

dag019 said:

I would occasionally have this problem with my TD5 and it was the fuel pump relay. Despite working when bench tested and having food connections (removed the pins and tightened the spades) it would still fail and a wiggle of the relay would rectify the issue. The relays are prone to internal failure and movement, something I picked up form @Brown. I currently have the same problem with my starer relay on my 110 (300tdi wiring). If you have confirmed you have power as above, then I would consider replacing the relay as a quick check before digging further into the wiring.

Click to expand...

Replaced the three relays under the seat next to the ECU with new ones + crimped the terminals in the holder a bit… No change..

Try resetting the fuel inertia trip on bulkhead, press the button at the base and then try to start her up.

Turned out to be the ECU…
Had a friend show up with his “special” one that has the immobilizer turned off in it and started straight away…

Was about to say, exactly the same symptoms and issues I posted about a few weeks ago.

Had my ECU put on test rig at ecutesting.com and confirmed failure, they rebuilt with lifetime warranty.

Working perfectly again.