Powertrain, generic (extended)

P2D87 Fan 1 Control Module Over Temperature

Check engine lightOn

EmissionsRelevant

Drive cycleNot required

Limp modeNo

Current electric radiator fans carry their own electronics, which turn the PWM or LIN request of the engine controller into motor current. P2D87 means this control module of fan 1 reports that it has become too hot. The supplier Brose, for example, rates its brushless fan modules with built-in LIN or PWM electronics for stable output up to 120 °C, so overheating points to a stiff or blocked motor drawing too much current, poor airflow at the radiator or an ageing power stage. No vehicle maker publicly documents P2D87 in this sense; Deutz uses the same number in its MD1 engine list for an unrelated fan drive output fault. CARB requires such output devices to be checked for correct response. A hot module usually cuts fan speed, so coolant temperature and air conditioning suffer. Fan 2 has P2D8A.

Likely causes

Worn bearings or debris make the fan motor stiff, so the module overheats from excess current

Clogged radiator or condenser fins, missing air guides, heat build-up at standstill

Ageing power stage or thermal contact inside the fan control module

Symptoms

Fan runs slower or switches off temporarily
Rising coolant temperature in slow traffic
Weaker air conditioning at standstill

Repair estimate

DifficultyMediumDIY possible

Parts and labour€150–800

Time1–3 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

fan control module 1wiring harnessecm

References: law.cornell.edu, brose.com, serdia.deutz.com.