Fuel pump relay
Fuel pump relay |
Fault symptom |
Fuel pump relay not working
Action |
1. |
Check
the voltage supply to the engine control system
Unplug connector H33-1. Connect the test lamp between H33-1, pin 30 and a safe grounding point. Turn the ignition key to the "ST" position (+50). The test lamp should flash during starter motor cranking. If the test lamp flashes, proceed to point 2. If the test lamp does not flash, proceed to point 4. |
2. |
Check the cable between connector H33-1 and
H33-4
Conduct a continuity test on the cable assembly between connector H33-1, pin 30 and connector H33-4, pin 11. The resistance should be < 1 Ohm. If the resistance is incorrect, take action on the cable assembly. If the resistance is correct, proceed to point 3. |
3. |
Check the cable assembly to the engine control
system
Conduct a continuity test on the cable assembly between connector H33-4, pin 11 and |
• |
Trionic control module, pin 56
|
• |
Motronic 2.10.2 control module, pin 3
|
6. |
Check the cable
assembly
Conduct a continuity test on the cable assembly between the fuel pump relay socket, pin 85 and connector H33-3, pin 29. The resistance should be < 1 Ohm. If the resistance is incorrect, take action on the cable assembly. If the resistance is correct, proceed to point 7. |
7. |
Check the cable assembly to the control
module
Unplug the control module. Conduct a continuity test on the cable assembly between |
• |
connector H33-1, pin 30 and the control module, pin
21.
|
• |
connector H33-3, pin 29 and the control module, pin 9.
The resistance should be < 1 Ohm. If the resistance is incorrect, take action on the cable assembly. If the resistance is correct, proceed to point 8. |
8. |
Final test
Start the car and check to see if the fault symptom remains. |