Citroen DS3 THP 150 - 2011 - P0245 Fault Code

[thunder87]

Dear Forum members,

I hope you can help me out as I myself and mechanics are already struggling with this issue.

Driving a DS3 THP 150 2011
10/2024 I had a leaky water pump resulting in engine overheating and slow crawling to mechanic.

- Waterpump replaced
- waterhose replaced
- thermostat replaced
- cooler replaced (was leaky too once systems filled up and checked under pressure)

So far so good but during testride mechanic noticed powerloss above approx 2500rpm. As long as you are driving in the city, not overtaking you wont notice that issue...no MIL, no Error in display shown!

Checked fault codes via OBD:
P0245 - Turbo Regulation solenoid valve control fault
Short ciruit to earth
I know there are already P0245 issues listed in this forum but only in combination with other codes

Deleting fault code does not help. It comes back right after starting the car (therefore assuming electrical issue like wire, ecu but not expecting turbo causing the issue - may be fully wrong)

- Wastegate solenoid replaced (did not change a thing)
- turbo checked visually, has free play, no scratches or similar visually at least
- checked wiring
- did some fog-test? checking for leaks (sry German native, not sure if it is called like that) - anyway, system seems leak tight

I am not an expert just giving hints on what I have heard what was tested

Mechanic saying next steps
- sending in ECO for checking (but does not expect ECO being faulty as it is pretty rare if so)
- replacing Turbo

I am really lost after 3 months now and the 2nd mechanic trying to figure out what may cause this issue

Not sure if it was caused by water leakage, overheating, or if issue was already there prior leakage...

Maybe you have already experienced sth similar or maybe a hint for me what else could cause this issue, maybe sth not being part of the actual circuit...?!

Many thanks in advance!
Florian

[xantia_v6]

Can you confirm that the wastegate solenoid that was replaced is the one under the manifold at the back of the engine (not the dump valve on the turbo body)?

Every other reference I find for this fault code on a PSA vehicle is for a diesel engine, so not applicable to your case, this also makes it a rare fault.

My guess is the while working on the engine, your mechanic has damaged the wiring harness that connectes to the boost control solenoid. The easiest way to check would be to measure the resistance back from the ECU connector. Maybe your mechanic has access to the wiring diagrams? I can probably find the diagrams but not today.

[thunder87]

Hi xantia_v6,

yes! It was replaced two times (2mechanics were working on it) already so faulty valve can be excluded I guess (pic attached)
I was told it is the one on the back left side standing in front of the car which controls the wastegate (not the one front right/centered)

Faulty wiring was already assumed after replacing valve without getting better therefore mechanic requested wiring diagrams.

I may doublecheck what wiring sheets he got and what exactly he measured - I found some online guessing they are the right ones?

https://www.peugeotforums.com/threads/m ... 99.370860/

[xantia_v6]

The pin connections for the boost solenoid are:

Where 1320 is the ECU and 1233 is the boost solenoid. 1270 is the control wire and the other is the supply.

With that fault present, the ECU is probably immediately going to a limp mode where it behaves as a non-turbocharged engine, but I don't understand why it is not putting on the engine warning light or beeping at you.

[thunder87]

Thanks for your quick answers, really appreciated!

Just to be clear: checking the ECU pin scheme for all 3 connectors I see A1, A2, A3

1270 connects between solenoid pin 2 and ECU B1, right?

Do I have to care about 1042B/1150A wire solenoid Pin 1 to ecu pin "5"? And if so is pin 5 on ecu "B5" as there is "A5" existing too?

Once checking wire(s) measuring between wire 1270 solenoid pin 2 and ecu wire B1 should be ~0 Ohms to realize wire is OK?

And yes, I don't have any further indication like MIL or Navi display error message or additional fault codes maybe also indicating that wire is okay but ECU not behaving as it should?!

If I would not have tried to overtake someone I would not have noticed this issue too.

[Gregor]

Do I have to care about 1042B/1150A wire solenoid Pin 1 to ecu pin "5"? And if so is pin 5 on ecu "B5" as there is "A5" existing too?

Once checking wire(s) measuring between wire 1270 solenoid pin 2 and ecu wire B1 should be ~0 Ohms to realize wire is OK?

In electricity there is always at least two wires. So connectors at solenoid are supply to power up-trigger the valve and you have to check bolth wires. El.charge can't move if any of the two wires is cut.
You should see measured value from one end to other end of the SAME wire approx. 0 ohm. I would disconnect conectot at solenoid and ECU, shorten bolth pins at solenoid end and measure resistance btw pins that go to ECU. And also btw. wire and ground point on chasis. That should be infiniteli big.

[thunder87]

Just a quick update from my side:

- wire harness was checked and found OK
- ECU sent in & Hardware issue noticed
-- ECU swapped by a replacement with a software copy of the original one
- Testride was OK yesterday
- driving to work today was great with having full power back but after 27km:
-- *beep*
-- Navi display: "Engine fault: Have the engine repaired"
-- SERVICE light on
-- OBD Error Code: "P0245 turbocharger wastegate solenoid B low"

Same code but behaviour different:

- SERVICE light and display warning occurs which didn't prior ECU replacement
- No powerloss (or maybe not that much like before)
- was able to clear fault code with OBD dongle/Torque app

Maybe a combination of faulty ECU & wire harness?