Test Description

WARNING: This page is about a different car, the 2003 GMC Savana and 2003 Chevrolet Chevy Express. However, it is still accessible from the selected car via links, so may be relevant.

The numbers below refer to the step numbers in the diagnostic procedure.

2

This step determines if the condition is present.

3

If any of the listed DTCs are set, diagnose those DTCs first.

5

This step tests the signal circuit of the Fuel Rail Temperature (FRT) sensor. The DVOM should display 5 volts.

7

This step tests the low reference circuit of the FRT sensor. An open FRT sensor low reference circuit may cause this DTC to set.

8

This step determines if the FICM, PCM, and the rail temperature output PWM circuit are OK. If the temperature parameter changes when the FRT signal circuit is grounded, the FICM, PCM, and wiring are OK. Repeat the procedure as necessary in order to verify correct operation of the FICM, PCM, and the rail temperature output PWM circuit.

9

This step verifies that the FICM is supplying the correct output voltage. The open circuit voltage should be 5.0 volts.