P1635

Diagnostic Chart:

Schematic:

CIRCUIT DESCRIPTION
The PCM provides a 5 volt supply for use in powering up sensors. This test monitors the voltage present at terminals BRD13 (shared by Boost and crankshaft position sensors) and BRD1 4 (optical/fuel temperature sensor (cam/hires).

CONDITIONS FOR RUNNING THE DTC
The ignition switch in the ON position.

CONDITIONS FOR SETTING THE DTC
5 volt reference is less than 1 volt.

ACTION TAKEN WHEN THE DTC SETS
^ The PCM will not illuminate the Malfunction Indicator Lamp (MIL).
^ The PCM records the operating conditions at the time the diagnostic fails. This information is stored in the Failure Records.

CONDITIONS FOR CLEARING THE MIL/DTC
^ A History DTC clears after forty consecutive warm-up cycles, if this or any other emission related diagnostic does not report any failures.
^ The use of a scan tool.

DIAGNOSTIC AIDS
During the time the failure is present, the setting of additional DTCs that share a 5 volt reference may also set.

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table.
2. Checks to confirm that a DTC is still present.
3. Checks to determine if there is a 5 volt reference from the PCM.
4. Checks to determine if there is a short-to-ground in the reference circuit or a short-to-ground in the PCM.
7. This step determines if the short is being caused by one of the sensors on the engine or the short is in the wiring harness.