DTC 20

DTC 20 Chart:

Fuel Pump Circuit:

Fuel Pump Relay Connector:

CIRCUIT DESCRIPTION
When the key is first turned "ON", the PCM turns the fuel pump control relay "ON" for two seconds to prime the fuel system for starting. If the engine is not cranked within two seconds of key "ON", the PCM turns "OFF" the fuel pump control relay until the engine is cranked. If the signal on the fuel pump feedback CKT 120 indicates that the fuel pump is "OFF" when fuel control pulses are being detected, DTC 20 will set.

DTC 20 WILL SET WHEN
- 4X fuel control pulses are being detected by the PCM.
- Fuel pump feedback voltage on CKT 120 is 2 volts or less.
- All above conditions are present for 1.3 seconds or more.

ACTION TAKEN (PCM WILL DEFAULT TO)
With a current DTC 20 set, the PCM will illuminate the Malfunction Indiactor Lamp (MIL) (Service Engine Soon).


DTC 20 WILL CLEAR WHEN
The fault no longer exists and the ignition switch is cycled "OFF" and "ON."

DTC CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.

1. Checks CKT 120 between fuel pump relay and in-tank fuel pump.
2. Checks B + and ground circuits for relay.
3. Checks B + and ground circuits for in-tank fuel pump.
4. Checks B + from PCM fuel pump control circuit to the relay.
5. Checks B + to fuel pump relay.
6. Checks for short to ground in CKT 120.
7. Checks fuel pump feedback circuit.