P1640

DTC P1640

CIRCUIT DESCRIPTION
The powertrain control module (PCM) contains an output driver module (ODM) that controls the following devices:
- A/C relay
- 1-2 shift solenoid
- 2-3 shift solenoid
- Torque converter clutch (TCC) solenoid

The ODM provides grounded output control of these devices through separate control circuits. The ODM monitors the voltage level at each of the control circuits when the device is commanded ON or OFF. Each ODM output has an internal feedback circuit that connects to the PCM microprocessor. The PCM monitors voltage through the ignition 1 voltage circuit. Excessive voltage or current may cause damage to the PCM. If the ODM detects excessive current or voltage on an output control circuit, this diagnostic trouble code (DTC) will set.

CONDITIONS FOR RUNNING THE DTC
The ignition is ON.

CONDITIONS FOR SETTING THE DTC
- The ODM has detected a voltage greater than 33 volts.OR
- Excessive current is detected on any circuit to ODM.
- The above conditions are present for 6 seconds.

ACTION TAKEN WHEN THE DTC SETS
- The control module stores the DTC information into memory when the diagnostic runs and fails.
- The malfunction indicator lamp (MIL) will not illuminate.
- The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records.
- The driver information center, if equipped, may display a message.

CONDITIONS FOR CLEARING THE DTC
- A current DTC Last Test Failed clears when the diagnostic runs and passes.
- A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.
- Clear the DTC with a scan tool.

DIAGNOSTIC AIDS
- A condition with the charging system may cause this DTC to set.
- For an intermittent condition, refer to Intermittent Conditions. Intermittent Conditions

TEST

Steps 1-7: