Peugeot 2008 - P1625 & P1621 (Intermittent)

[Semihcan]

Hello, I need your help. I purchased a second-hand 2016 Peugeot 2008 1.6 BlueHDI ETG6 with a gearbox. The vehicle also passed the inspection.

However, on the day I bought it (January 22, 2025), while heading to the service to have the necessary maintenance done as a precaution, the following issues appeared:

- Automatic Emergency Braking System Fault
- Engine Fault
- ESP/ASR System Fault
- Reverse Assistance System Fault

The vehicle suddenly lost power and started to misfire. It was a very stressful situation in highway traffic. I managed to pull over to the right lane with the hazard lights on. When I turned the ignition off and back on, the faults disappeared, and I was able to drive to the service with the hazard lights still on.

At the service, the Peugeot PC was connected, and based on the error codes, we changed the EFG battery to AMG. The crankshaft position sensor and its connector were also replaced due to potential contact issues. The issue was not resolved.

DTC Codes:
ECU: P1625 - P1621
Gearbox: U1208 - U1213
ABS/ESP: U1208
LIDAR: U1F79 81

Since the car also displayed an automatic braking system error, I suspected there might be an issue with the Active City Brake sensor, so I disabled the Active City Brake feature in the settings. The issue still wasn't fixed.

Last week, I took the car to an authorized service. Upon inspection, they said the injectors need to be replaced or refurbished. However, there is no rough running or disturbing engine noise in my car. After refurbishing the injectors, the issue remained. Now they will try replacing the fuel pump and sensor. I am waiting for an update.

The car sometimes activates the warning lights, loses power, and starts misfiring, but this can happen after a few hours or a few days. Since the exact conditions for this to happen are unclear, it poses a serious safety risk. It's impossible for me to go on the highway with this issue.

If anyone has had similar issues in the past, I would greatly appreciate your help and guidance on how it was resolved. This process has mentally exhausted me. My prayers are with all of us...

[Semihcan]

Can you help me with the descriptions of the fault codes to find the cause of the problem?

[GiveMeABreak]

First all the following you list:
- Automatic Emergency Braking System Fault
- Engine Fault
- ESP/ASR System Fault
- Reverse Assistance System Fault

... will be as a consequence of a fault with the ESP system as all these functions rely on that to work correctly, including the electronic parking brake in automatic mode.

You have a lot going on here, but here are some of the faults:

C1651 86 Tyre under-inflation detection reset request signal fault: Absence of response from the ESP ECU (again this can be because of the ESP fault as above)
B1331 15 Electric windows authorisation fault: Short circuit to positive or open circuit (separate issue).

Fault Code:	P1625
Description of Fault:	Computer: Software redundancy fault; Calculation error detected. Fault inside the engine ECU detected.
Conditions for Fault to clear:	Manual clearing of the fault then starting of the engine
Downgrade Modes whilst Fault is active:	Engine stopped Switching on of the warning lamp and/or warning message Warning lamp STOP
Symptoms:	Jerking/stalling Starting problem Lack of power
Suspect Areas:	Engine ECU

Fault Code:	P1621
Description of Fault:	Computer: Software redundancy fault at the injection (Level 2). Malfunction internal to the engine ECU on the torque calculation functions.
Conditions for Fault to clear:	Manual clearing of the fault then starting of the engine
Downgrade Modes whilst Fault is active:	Switching on of the warning lamp and/or warning message "SERVICE" warning lamp
Symptoms:	Jerking/stalling Starting problem Lack of power Absence of automatic stopping of the internal combustion engine (Vehicle equipped with "stop and start") Problem with automatic restarting of the internal combustion engine (Vehicle equipped with "stop and start")
Suspect Areas:	Engine ECU

Fault Code:	U1213
Description of Fault:	Fault with the information sent by either the ABS/ESP ECU or the electric parking brake ECU : Value received incorrect. Absence, or wrong value, for the CAN information containing the electric handbrake status, the torque requested by the ESP ECU, or the rear wheel speeds. Context of appearance of the fault code: Ignition on Technical precision on the context of appearance of the fault code Supply voltage correct Absence of fault codes U1000 - U1003 - U1113 The system is not in starting phase
Conditions for Fault to clear:	Reception of 20 consecutive items of valid information
Downgrade Modes whilst Fault is active:	Possibility 1 Electric parking brake: Invalid signal - Engine running or in Stop and Start phase ; Replacement value : Brake activated - Engine stopped and not in Stop and Start phase ; Replacement value : Brake deactivated - Crawling deactivated Possibility 2 - Signal for the torque requested by the ESP ECU : Prohibited value - Replacement value : 0 Possibility 3 Signal for the rear RH/rear LH wheel speeds : Invalid signal - Calculation of the replacement value from the vehicle speed
Symptoms:	Difficult/impossible to change a gear Lack of power
Suspect Areas:	28-way harness of the piloted manual gearbox ECU ABS/ESP ECU Electric parking brake Controlled manual gearbox ECU