P15D5

20A902 - P15D5

Information saved in
DME

Fault code
20A902 - P15D5

Fault text
Coolant pump, operation with reduced output: Undervoltage
detected

Fault description
The diagnostic function monitors the voltage of the water
pump.

Condition for fault identification
Test condition:
The fault is recognized when the water pump's voltage is
less than 10 V.
Potential problem source(s):
- Systematic fault in vehicle, related to battery condition,
etc.
- Defective water pump
Terminal condition: none
Voltage condition:
- Electrical system voltage > 10 V
Temperature condition:
- None
Time condition:
- None
Other conditions:
- Engine on
- No BSD fault, no alternator fault

Condition for fault memory entry
This fault is logged in the control module's fault memory if
it remains present for longer than 10 sec.

Action in service
- If the 'undervoltage' diagnostic fault code is stored in
several control modules, this relates to a systematic fault in
the vehicle (such as unsatisfactory battery condition). Carry
out the following test module (ABL): Energy diagnosis.
- If the only diagnostic fault code is logged for the water
pump, then the problem lies with the power-supply voltage
- Replace water pump

Fault effect and breakdown warning
Breakdown notice:
- none
Possible apparent symptoms:
- Engine can overheat

Driver information
Warning light:
- ECE emissions warning lamp: off
- US emissions warning lamp: off
- ECE electronic engine power reduction: off
- US electronic engine power reduction: off
- CC message: none

Service instruction
- none