P019

Circuit Description

The PCM monitors fuel pump feedback voltage for 6 seconds after the ignition is turned 'ON' without the engine being cranked. The fuel pump relay will be energized for 2 seconds and then deenergized. If the voltage on the fuel pump feedback never drops below 7 volts during the first 6 seconds, Code P019 will set indicating voltage on CKT 120 with the fuel pump relay deenergized.

Test Condition(s)

1. Code P012, P014 AND P015 not set.
2. Coolant temperature 50°C or greater.
3. No 4X reference pulses detected since key on (engine not being cranked).

Failure Condition(s)

Fuel pump feedback voltage remained above 7 volts for 6 seconds after ignition 'ON' (fuel relay never deenergized).

Action Taken

1. PCM turns 'ON' the 'SERVICE VEHICLE SOON' message.

Notes on Fault Tree

1. With the key 'ON', engine 'OFF', parameter PD1O, battery voltage, should read 0 volt (fuel pump relay deenergized). If PD10 shows voltage greater than 7 volts, the cause of voltage on CKT 120 must be repaired.
2. Checking for a shorted oil pressure switch.
3. Checking for shorted fuel pump relay.
4. Checking for voltage on CKT 120 at the PCM.
5. Checking for proper control of the fuel pump relay A by the PCM.

Notes on Intermittents

If when the ignition is turned 'OFF' and the oil pressure telltale or message does not light, check for the oil pressure switch intermittently stuck closed.

Also, code could be setting due to a sluggish or intermittently stuck fuel pump relay.