Peugeot 207 & 206 engine ECU with common water damage

This water damaged ECU is a very common failure for Peugeot 206 & 207 vehicles built between 2005 and 2011. The common issue is caused by engine coolant contamination into the wiring harness that travels via ‘capillary action’ up to the plug of the ECU, once the water from the coolant system reaches the ECU it causes the ECU terminals to corrode causing open circuits for various sensors and actuators, this results in host of running problems for the engine.

The most common issues seen are engine misfires, engine not revving properly due to throttle position faults, engine won’t start or cuts out, and normally the Anti-pollution light will also be illuminated on the instrument cluster.

When diagnosing, the fault using a diagnostic scanner there will usually be fault codes stored for the throttle position sensors, injector circuits, coolant/air temperature sensor faults or O2 sensor faults. Often the fault is initially misdiagnosed since the fault codes are blaming other sensors on the car, which can lead to replacing these sensors unnecessarily before identifying that the ECU is the cause of the fault.

This is caused by fluid from the coolant system getting into the main engine wiring harness that travels along and into the ECU. Once the fluid has made its way to the ECU it then causes the corrosion to the pins and internal hardware which causes a high resistance or open circuit for various engine sensor/actuator circuits resulting in the running symptoms described before.

Solution

We no longer offer service on this system type. Instead, these are still available from the main dealer to purchase, or you can purchase a used replacement and have the key coding swapped from your original using dealer-level diagnostic equipment.

Common Failure symptoms:

• Engine misfire
• Throttle problems
• Engine cutting out
• Engine will not start
• Fault codes for throttle position sensors
• Fault codes for coolant temp sensor
• Fault codes for O2 sensor

Common fault codes:

• P0121 – Signal Incoherence Between Motorised Throttle Signals 1 And 2
• P1161 – Throttle Position Regulation
• P1631 – Engine ECU Internal
• P1340 – Engine Misfire Detected
• P0123 – Throttle Position Sensor
• P2176 – Programming of The Motorised Throttle Limp Home Coherence
• P0135 – O2 Heating Implausible Signal
• P0115 – Engine Coolant Temperature Sensor Fault
• P0110 – Intake Air Temperature Sensor Circuit Fault

Affected Vehicles:

• Peugeot 206 (2006 – 2009)
• Peugeot 207 (2007 – 2011)
• Peugeot 1007 (2005 – 2010)
• Peugeot Partner (2005 – 2011)

Common failing part numbers:

HW9651696680 / 7052754374 / 7052 754374 / 7332434979 / 7332 434979
6287628749 / 6287 628749 / 6192553788 / 6192553788
6100269889 / 6100 269889 / SW9664127180 / SW9663306680 / SW9661961280
SW9661700480 / SW9660374680 / SW9665424480 / 7288005632

215860489A / 21586048-9 A / 215859329A / 21585932-9 A / 215857854A
21585785-4 A / 215859001A0 / 215859001 A0 / 215865398A
21586539-8A / 81554141206 / 8154 141 206 / 215855983A0
21585598-3 A0 / 215862398B / 215862398B / 21586048-9A