3. Connect ohmmeter to special tool 9637, pin II/20, and ground.
Display: infinity ohms
If 0 - 5 ohms is displayed, check wiring for chafing and pinching damage.
5 Check wiring from DME control module to relay for short circuit to B+.
1. Connect special tool 9637 to wiring harness (DME control module connector).
2. Remove relay.
3. Connect voltmeter to special tool 9637, pin II/20, and ground.
Ignition on.
Display: 0 V
If battery voltage is displayed, check wiring harness for chafing and pinching damage.
Engine Compartment Purge Fan Output Stage - Below Limit
P1674
Engine Compartment Purge Fan Output Stage - Below Limit
Function
An engine compartment purge fan is installed to reduce the engine compartment temperature. The engine compartment purge fan is triggered by the
DME control module as a function of the engine temperature, engine compartment temperature and vehicle speed.
Short circuit to ground and open circuit are detected when the output stage is blocked, short to B+ when the output stage is conducting.
Diagnosis conditions
- Engine running
- Battery voltage greater than 7 V
- Engine compartment purge fan switched on once
NOTE: The triggering wire for relay terminal 85 is monitored.