Low Fuel Lamp/Indicator: Testing and Inspection
The content of this article reflects the changes identified in SN031015Low Fuel Indicator Troubleshooting
If the low fuel indicator is blinking, do this:
1. Close the manual shut-off valve.
2. Remove the PGM-FI main relay 2 (A).
3. Turn the ignition switch ON (II).
4. Measure voltage between PCM connector terminal E28 and body ground.
Is there more than 3 V?
YES - Go to step 5.
NO - Update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck.
If the symptom/indication goes away with a known-good PCM, replace the original PCM.
5. Disconnect the fuel pressure temperature sensor 2P connector. In a well-ventilated area, loosen the fuel temperature sensor until fuel starts to vent. When the fuel stops venting, go to step 6.
6. Measure voltage between PCM connector terminal E28 and body ground.
Is there more than 3 V?
YES - Go to step 7.
NO - Replace the P1 fuel pressure regulator. Then disconnect the negative cable from the battery for a few seconds to reset the blinking low fuel indicator.
7. Turn the ignition switch to Lock (O).
8. Disconnect the fuel pressure regulator switch 2P connector.
9. Check for continuity between fuel pressure regulator switch 2P connector terminal No.2 and body ground.
Is there continuity?
YES - Go to step 10.
NO - Repair open in the wire between the fuel pressure regulator switch and G201. Then disconnect the negative cable from the battery for a few seconds to reset the low fuel indicator.
10. Measure voltage between fuel pressure regulator switch 2 P connector terminal No.1 and body ground.
Is there more than 3 V?
YES - Go to step 11.
NO - Repair open in the wire between the fuel pressure regulator switch and PCM (E28). Then disconnect the negative cable from the battery for a few seconds to reset the low fuel indicator.
11. Substitute a known-good fuel pressure regulator switch. Then disconnect the negative cable from the battery for a few seconds to reset the low fuel indicator.
Does the low fuel indicator continue to blink when you reconnect the battery?
YES - Do a leak inspection. If there is no leak, update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM.
NO - Replace the original fuel pressure regulator switch. Then disconnect the negative cable from the battery for a few seconds to reset the low fuel indicator.