U1208 no communication with engine ecu

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gijoe50000
Posts: 4
Joined: 19 Nov 2016, 23:45
Location: Clonakilty
My Cars: 407 SW SE 1.6hdi 2006

U1208 no communication with engine ecu

Post by gijoe50000 »

So I've been having an ESP issue for ages now and can't figure it out.
All my live graphing values in Diagbox are fine, it reads all wheel speeds, steering wheel angle sensor, yaw & transverse acceleration, brake pressure, lights, accelerator position, engine speed, voltage etc. Cruise control works fine too, which rules out some more things like brake pedal switch etc.

I'm trying to track down what the problem actually is. I have no other problems with the car, all the power and grounds on the ABS block are good, I assume there's communication on the can since everything seems to be reading fine.
The fault code U1208 is a bit vague.. does it mean the BSI has no communication with the engine ecu ?(I'm thinking 'no') Or the esp/abs has no communication with the engine ECU?

I know from looking at the Sedre diagrams that the ABS/ESP ECU has a direct output to the diagnostic connector. Is it possible that the values I'm seeing in Diagbox are just coming straight from the ABS/ESP ECU instead of going through the BSI? I can run the actuator tests on the ABS block too, no bother.. so it's not totally dead anyway.. Anyone?
ell270390
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Re: U1208 no communication with engine ecu

Post by ell270390 »

esp/abs has no communication with the engine ECU. What model is the vehicle?
RichardW
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Re: U1208 no communication with engine ecu

Post by RichardW »

Check in the engine ECU for faults - are there any EGR ones recorded? One of the early EGR faults disables the ESP, but doesn't put the EML on!?!?! French logic.... Spent ages tracking down why our C4 Pic kept putting the handbrake warning on, only to eventually twig that it was the EGR valve :roll:
Richard W
gijoe50000
Posts: 4
Joined: 19 Nov 2016, 23:45
Location: Clonakilty
My Cars: 407 SW SE 1.6hdi 2006

Re: U1208 no communication with engine ecu

Post by gijoe50000 »

ell270390 wrote:esp/abs has no communication with the engine ECU. What model is the vehicle?
Car is a 407 1.6hdi 2006.
The esp has communication with the engine ecu alright as far as I know. It receives the engine torque, and the 'drivers wish' torque, both are graphed in Diagbox under esp, and both are reading a constant 408nm. Which is either a safety/bogus value, or else the engine ecu has errors.
RichardW wrote:Check in the engine ECU for faults - are there any EGR ones recorded? One of the early EGR faults disables the ESP, but doesn't put the EML on!?!?! French logic.... Spent ages tracking down why our C4 Pic kept putting the handbrake warning on, only to eventually twig that it was the EGR valve :roll:
I'm not getting any EGR errors but I think the previous owner has it disabled, looks like a plate has been inserted in between it, and I don't even get any EGR errors when I unplug it. Diagbox does give a few "invalid value"s for a few of the egr variables in Diagbox like electrovalve, and throttle electrovalve. They also read -1% somewhere else, peugeot planet maybe, or else when graphing..

The esp light did disappear for a few seconds a few days ago, when driving, which it has never done before, which was kind of strange. I've pulled the bin file with MPPS but it's going to take me a while to make any sense of it. Have to bring it in to be retested for the NCT in a few days so even if I got it temporarily disabled for a few days I'd be happy!
gijoe50000
Posts: 4
Joined: 19 Nov 2016, 23:45
Location: Clonakilty
My Cars: 407 SW SE 1.6hdi 2006

Re: U1208 no communication with engine ecu

Post by gijoe50000 »

I only saw these messages today, I didn't have email notifications enabled on my profile! Thanks for the replies, any thoughts are appreciated..
All the wiring seems good too at the abs/esp block.. comms (~2.5v), grounds (0v-0.01v), power(12v-14v) etc..
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