VOLVO
IEM-P117147 - Rotor Sensor. System Internal Failures. Watchdog / safety µC failure
System
Unknown System / Manufacturer Specific
Volvo models this fault code applies to
Applies to the following models:
1 modelV60 (2011–)
Show models by year and engine (2)
What does this fault code mean?
Although the code is named watchdog fault, it applies when the speed from the electric rear axle (ERAD) differs too much from the wheel speed reported by the BCM (brake control module), while the clutch in the ERAD is engaged. The fault is set while driving in gear D or R. It is a safety-related fault, and electric propulsion is then not possible.
Possible causes
- The angle sensor is damaged
- Loose contacts, contact resistance or oxidation at the connections between the ERAD and the voltage converter (ISC), or damaged wiring between them
- The signal cable is short-circuited to ground or to supply voltage, or has an open circuit
- Open circuit or short to ground or supply voltage in the clutch control for the electric rear axle (DCC)
- The clutch in the ERAD has mechanical damage
- Incorrect wheel speed signals from the BCM or a software fault in the electric rear axle drive control module (IEM)
What you can do
- 1Have a workshop check the angle sensor, the clutch and the wiring between the electric rear axle and the voltage converter (ISC). High voltage systems may only be handled by qualified personnel
- 2Have a workshop read the fault codes in the brake control module (BCM) if wheel speed faults may be the cause. Do not change anything yourself in the brake system
- 3If you have a diagnostic tool: compare the rear axle speed in live data with the wheel speed during a drive in gear D or R
- 4After the repair, check that the code is not stored again while driving
Symptoms you may notice4
- Text window and warning symbol with a text message
- Drive mode PURE disengages automatically or is unavailable
- Drive mode AWD disengages automatically or is unavailable
- Drive mode HYBRID: the combustion engine runs all the time or too often
What the fault can affect2
- Electric propulsion is not possible
- Brake energy regeneration from the electric rear axle is not possible
General guidance for car owners. Diagnosis on the car can point to a different cause.