P1601

DIAGNOSTIC TROUBLE CODES P1601, P1602
Fuel pump relay, control module output, no continuity or shorting to ground/batt+

Fault Symptom.
Engine fails to start.

Condition
In the event of a short circuit or open circuit a diagnostic trouble code will be generated.

Diagnostic Procedure.
1. Check the fuel pump relays electrical interface.
Remove the relay board and take out the fuel pump relay.
Check the following three steps:
^ Connect the test lamp across pin 86 and a good ground.
The test lamp should light up when the ignition switch is in the ON position.
When the ignition switch is turned to the OFF position the test lamp should go out five seconds afterwards.

If the test lamp does not work, check the lead between pin 86 of the fuel pump relay and crimped connection J37.

On cars equipped with an anti-theft alarm, the control module for the alarm forms part of the electrical circuit.

If the anti-theft alarm functions are suspected of being at fault, repair as necessary.





^ Relay winding resistance measurement.
Measure the resistance across pins 85 and 86 of the relay.
The resistance should be about 85 ohms.

If it is not, fit a new relay.

^ Check the lead between pin 85 of the relay base and pin 3 of the control module for continuity shorting.

If all the results are OK, continue with step 3.

2. Clear the diagnostic trouble code and drive the car to see whether the DTC is generated again.

If the diagnostic trouble code is generated again, continue at "Procedure Before ECM Replacement". Component Tests
If the trouble code is not generated again the remedial measure taken was correct, otherwise the fault is of intermittent type.