Fuel Pump Relay/Fuel Pump Test

Symptom Of Fault.
Engine will not start.





Diagnostic Procedure.
1. Check the operation of the fuel pump relay
- Connect an ISAT scan tool.
- Ignition switch in ON position.
- Select "ACTIVATE".
- Select "PUMP RELAY".
The main relay is activated for 10 seconds at a frequency of 1 Hz. If a longer activation time is required, the command will have to be repeated.
- Listen for the sound of the fuel pump relay and fuel pump working. They should both be heard working at a frequency of 1 Hz (once a second).

Can only the relay be heard?
YES:
^ Continue with point 2.
NO:
^ Neither the relay nor the pump can be heard. Continue with point 7.

2. Check the fuse
- Check fuse 14 and change it if necessary.

Is the fuse OK?
YES:
^ Continue with point 3.
NO:
^ If the fuse blows on repeated activation of the fuel pump relay by means of the ISAT scantool, continue with point 6.





3. Check the fuel pump
- Forcibly supply the fuel pump with power.
- Connect a jumper lead between fuses 14 and 22.

Does the fuel pump work?
YES:
^ Continue with point 4.
NO:
^ Continue with point 5.

4. Check the fuel pump relay
- Unplug the fuel pump relay.
- Connect a jumper lead between pins 30 and 87 on the relay holder.

Does the fuel pump work?
YES:
^ Change the fuel pump relay.
NO:
^ Check the lead between pin 87 and fuse 14 and the lead between pin 30 and battery positive (B+). Repair or replace the leads if necessary.





5. Check the fuel pump
- Unplug connector H4-4 from the fuel pump. The connector is located adjacent to the fuel pump under the luggage compartment floor.
- Connect the test lamp to pins 1 and 2 of the 4-pin male connector.
- Select "ACTIVATE".
- Select "PUMP RELAY".
The test lamp should flash at the rate of 1 Hz (once a second).

Does the test lamp flash?
YES:
^ Change the fuel pump.
NO:
^ First check and if necessary rectify the lead between pin 2 and grounding point G5. If this does not help, deal with the lead between pin 1 and fuse 14 in the same way.





6. Check the fuel pump
- Unplug connector H4-4 from the fuel pump. The connector is located adjacent to the fuel pump under the luggage compartment floor.
- Change fuse 14 and repeat the ISAT scan tool command "PUMP RELAY".

Did the fuse blow?
YES:
^ Check and if necessary rectify the wiring harness between fuse 14 and pin 1 of connector H4-4.
NO:
^ Change the fuel pump.

7. Check the fuel pump relay
- Unplug the fuel pump relay.
- Connect the test lamp to pins 85 and 86 of the relay holder.
- Ignition switch in ON position.
- Select "ACTIVATE".
- Select "PUMP RELAY".
The test lamp should flash at the rate of 1 Hz (once a second).

Does the test lamp flash?
YES:
^ Change the fuel pump relay.
NO:
^ Continue with point 8.





8. Check the fuel pump relay's power supply
- Connect a test lamp to pin 86 of the relay holder and a good grounding point.

Is the test lamp on?
YES:
^ Continue with point 9.
NO:
^ Check and if necessary repair or replace the lead between pin 86 of the relay holder and battery positive (B+).

9. Check the fuel pump relay's connection to ground
- Check the lead between pin 85 of the relay holder and pin 56 of the control module.

Is the lead OK?
YES:
^ Proceed at "Before Replacing a Control Module". Component Tests and General Diagnostics
NO:
^ Rectify the fault.