DTC P1669, P1670, P1671: ECM COOLING FAN CIRCUIT MALFUNCTION
On Range Rover, the ECM is located at the left corner of the engine compartment inside an " E" box. The ECM " E" box is equipped with a cooling fan that provides cooler cabin air into the " E" box to provide a cooler environment for the Bosch Motronic 5.2.1 ECM. &Quot; E" box cooling fan operation is controlled by the ECM. The operating temperature of the ECM is monitored by an internal temperature sensor which it uses to determine when " E" box cooling fan operation is necessary.
When cooling fan operation is needed the fan is grounded through ECM 40-pin connector C0637 terminal No. 10 (Black/Pink wire). Battery voltage for cooling fan is provided from fuse No. 26 (20-amp) located in engine compartment fuse/relay box via Brown/Pink wire.
If there is an " E" box cooling fan malfunction the MIL will illuminate and the following DTCs may be set: If DTC P1669 is set, the ECM cooling fan circuit malfunction.
If DTC P1670 is set, the ECM cooling fan circuit low.
If DTC P1671 is set, the ECM cooling fan circuit high.
Diagnosis & Repair
Ensure " E" box cooling fan is operating properly. Check for opens or shorts. Check for poor connections and/or loose wires at ECM. See appropriate wiring diagram in WIRING DIAGRAMS article. Repair as necessary. When DTCs P1669-P1671 repairs are completed, perform REPAIR CONFIRMATION DRIVE CYCLE " A" .