Toyota Yaris 2010 - Multiple ECU faults all at once. Dead car on M6 !

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Sun 9 Dec 2018 11:38
Toyota Yaris 2010 - Multiple ECU faults all at once. Dead car on M6 ! - Greg-75

On Wednesday my Yaris totally died on the M6 in the wet.

It's done it a few times in VERY WET motorway driving that it has stumbled and lost power (felt like fuel starvation but hard cuts, proper jerking) ECU light on and then it's fixed itself. Couldn't get to the bottom of it but suspected it was water getting in and interfering electrically somewhere.

This time it's totally dead. Same thing jerking and loss of power / inability to rev up properly but now it won't restart, even after drying out and I have 5 permanent and seemingly unrelated faults up at once where there were none at the start of the journey.

I've got:

P 1271 - Accelerator position

P 0089 - Suction control valve stuck (diesel pump)

P 0045 - Turbo boost sensor

P1228 - Injector short / intermittent fault

P0252 - Injection pump fuel metering control

These all seem pretty unrelated, have also seen ones for Mass air flow sensor and cam phase sensor come up after cranking etc.

Seems like a wiring fault somewhere? Any ideas for further investigation? I've had a good look at loom where I can access it. No big plugs seems intact everywhere and all the plugs are ampseal type ones, well sealed and clean and dry when I remove and reseat them..

Help!!

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Sun 9 Dec 2018 11:44
Toyota Yaris 2010 - Multiple ECU faults all at once. Dead car on M6 ! - Greg-75

Just tried cranking again and the cam position sensor fault has come back up.

The others survive a reset of the codes, come back immediately at key on.

Have also had EGR and Glow plug circuit A faults up during testing as well.. ??

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Sun 9 Dec 2018 19:16
Toyota Yaris 2010 - Multiple ECU faults all at once. Dead car on M6 ! - daveyjp
Before guessing and relying on codes do the basics first. A full battery and charging system check.

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Sun 9 Dec 2018 19:52
Toyota Yaris 2010 - Multiple ECU faults all at once. Dead car on M6 ! - SteveLee

It could well be the cam position sensor going bad. Once running an engine will run with a cam sensor giving bad info - but it won't start because the ECU does not know what phase the engine is in. Most engines will start and run (with reduced power) with a bad crank position sensor because the crank and phase of the engine can be derived from the cam position sensor signal.

It could just be a dodgy connector allowing the ingress of water. Most of these hall type sensors start to fail when they are hot, and then work again when they cool down, eventually failing when cold too.

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Sun 9 Dec 2018 20:23
Toyota Yaris 2010 - Multiple ECU faults all at once. Dead car on M6 ! - elekie&a/c doctor

I can't really see any of those faults causing a completely dead engine while running. The common factor here is the engine ecu. Unlikely to be the actual Ecu at fault ,more likely to be a power or earth circuit failure,or an engine control sensor short circuit fail. I would check the earth points on the engine.

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Mon 10 Dec 2018 14:01
Toyota Yaris 2010 - Multiple ECU faults all at once. Dead car on M6 ! - yokel38

Worth checking rainwater isn't leaking into the front kick panels, all sorts of electrical gubbins hidden away in there just awaiting a short circuit. Not a common fault, but I have come across this once or twice.

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Mon 10 Dec 2018 16:10
Toyota Yaris 2010 - Multiple ECU faults all at once. Dead car on M6 ! - dieselnut

As the problem is related to it raining each time.

Check water hasn't got into the ECU itself or the main ECU plug.

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Mon 10 Dec 2018 17:36
Toyota Yaris 2010 - Multiple ECU faults all at once. Dead car on M6 ! - Andrew-T

As the problem is related to it raining each time, check water hasn't got into the ECU itself or the main ECU plug.

Some cars suffer if the drainage from the rainwater scuttle in front of the screen gets blocked. Don't know about the Yaris tho.

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