206 1,4 hdi - electrical fault, possibly engine run signal

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Mon 21 Dec 2015 04:54
206 1,4 hdi - electrical fault, possibly engine run signal - andyvernon

Having trouble with a 206 1.4 hdi 2005, runs ok for a few minutes or more and then I loose heater blowers, rev counter, rear heater, coolant temp guage.

I have checked the engine fuse box and even swaped it for a known good unit. On this box is the heater blower fuse and relay and when the fault is occurring I have a power to the relay but do not have an earth! I am guessing that it's either the engine running signal or something after that but I can not find out where the system gets its signal from for engine running to power all these components up and where it goes after.

Anyone help please


Edited by andyvernon on 21/12/2015 at 04:55

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Mon 21 Dec 2015 10:15
206 1,4 hdi - electrical fault, possibly engine run signal - elekie&a/c doctor
I would check the main earth leads,especially the main battery to chassis cables under the battery tray and those bolted to the top of the gearbox.
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Mon 21 Dec 2015 12:02
206 1,4 hdi - electrical fault, possibly engine run signal - Peter.N.

Check you have about 14.4 volts across the battery when the fault occurs, you could have an alternator problem.

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Tue 22 Dec 2015 06:10
206 1,4 hdi - electrical fault, possibly engine run signal - andyvernon

Checked , cleaned and remounted earth's also checked the alternator output and while the problem is occurring I still have 14.4V

The blower relay is on the engine fuse box circuit board but whilst the problem is occurring it does not receive the signals to operate. As far as I can see the board controls this but the main fault I have is all items that operate once engine is seen as running are not operating so Im thinking if I knew where the signal input comes from for engine running ie. Crank sensor or alternator etc and where it goes to. If it's the ecu or bsi that sees the signal and then processes it. So then I can check the signal, wiring and connections to decide whether it's the input or the processing of the input. If I'm making sense to anyone.

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Tue 22 Dec 2015 10:30
206 1,4 hdi - electrical fault, possibly engine run signal - elekie&a/c doctor
I can see exactly where you coming from with this.I suspect that the engine run signal is networked to the cabin bsi ,possibly via the can system.( or van in the case of Peugeot ).also the electric system will go into economy mode if the engine is not run and some functions will not operate eg Windows.If this function works ,then perhaps the engine run signal is being processed.Perhaps there is a wiring fault between the engine bay and cabin electrics.An accurate wiring diagram may be helpful but difficult to get.
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Wed 23 Dec 2015 23:09
206 1,4 hdi - electrical fahult, possibly engine run signal - andyvernon
I can see exactly where you coming from with this.I suspect that the engine run signal is networked to the cabin bsi ,possibly via the can system.( or van in the case of Peugeot ).also the electric system will go into economy mode if the engine is not run and some functions will not operate eg Windows.If this function works ,then perhaps the engine run signal is being processed.Perhaps there is a wiring fault between the engine bay and cabin electrics.An accurate wiring diagram may be helpful but difficult to get.

Excellent thanks, that's sher I'm at now, I've got a couple off diagrams but as you say an accurate one I cannot find! I am learning a lot on this job and yes I've got to the point that it's either the CAN or the ECU because I have a PD003 can communication fault, no communication on the engine ecu and a P0500 Vehicle speed signal Incorrect signal fault.

I have checked the live data and the engine ecu states 12 mph and also states the brake pedal is pressed when not!

I then checked the ABS Ecu and that says 0mph and states the pedal as depressed and changes correctly when pressed.

So it's either receiving incorrect data through the CAN or its had it.

Although thinking as I'm typing the brake pedal sensor has 2 outputs, one direct to the engine ecu and I have checked that and it changes 0 - 12v relative to pedal position. So surely that shows ecu fault?

The other output goes apparently to the bsi but I have not checked or proven it does and that the diagram is correct. I have checked it's switching output at the sensor itself and it's OK.

But that then I'm still confused as to it being a bsi error or ecu error as I do not know if it could be the bsi knackered and sending faults or incorrect volts, signals etc to the ecu. ?

Wow this hurts my head!

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