Powertrain
generic / SAE
P25AF
Coolant Temperature Control Module Requested MIL Illumination
A dedicated coolant-temperature control module (used on engines with electric coolant pumps and electronic thermostats to keep the cylinder head and block at independent setpoints) has requested the ECM to illuminate the MIL because of an emissions-relevant fault on its side. Original fault is in that module.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number5 / AF
Possible causes
- Internal fault — read the module DTCs high
Inspection / repair
- Difficulty: medium
- DIY: shop recommended
- Estimated cost: 80–1200 €
- Estimated time: 0.5–4 h
- Component: coolant temp control module
- MIL / check engine light
- emissions-relevant
Sources
References
sae:J2012