P1502

Diagram Chart:

Diagnostic Chart:

Electrical:

CIRCUIT DESCRIPTION

This DTC will set if the ECM has not been programmed with the frequency code of the Theft Deterrent Module, or if there is a problem with the circuit used for transmitting the data (the Vehicle Speed/Theft Deterrent Signal circuit).


CONDITIONS FOR RUNNING THE DTC

Engine cranking

CONDITIONS FOR SETTING THE DTC

The ECM has not received the frequency code from the Theft Deterrent Module.

ACTION TAKEN WHEN THE DTC SETS

The ECM will not illuminate the Malfunction Indicator Lamp (MIL).

CONDITIONS FOR CLEARING THE MIL/DTC

^ The DTC clears after forty consecutive warm-up cycles if no failures report by this diagnostic or any other non-emission related diagnostic.

^ The ECM battery voltage is interrupted.

^ The scan tool clears the MIL/DTC.

DIAGNOSTIC AIDS

If the ECM and the Theft Deterrent Module have not been properly programmed, this DTC may set and the vehicle will not start. Refer to Antitheft and Alarm Systems for programming instructions.

TEST DESCRIPTION

The number(s) below refer to the step numbers on the diagnostic table.

2. This step verifies whether or not the ECM is receiving vehicle speed data.

3. The test light that is connected to B+ is used to simulate the B+ pull-up within the ECM. The DVM can be connected to the shaft of the test light and battery ground.

5. With the signal generator set to 600 Hz, the scan tool should indicate about 56 mph.