Transmission Diagnosis

DTC P0562





Circuit Description
The transmission control module (TCM) samples the system voltage on the Ignition 1 circuit every 0.1 seconds. Lower than normal voltage may be inadequate to operate the transmission control solenoids properly. Improper solenoid operation may cause erratic transmission operation, which may result in internal damage.
If the TCM detects low voltage, DTC P0562 sets. DTC P0562 is a type A DTC.

DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P0562 System Voltage Low

Conditions for Running The DTC
The engine speed is greater than 1,200 RPM.

Conditions for Setting The DTC
The TCM detects system voltage is 8 volts or less for 20 seconds.

Action Taken When the DTC Sets
^ The TCM requests the engine control module (ECM) to illuminate the malfunction indicator lamp (MIL).
^ The TCM commands maximum line pressure.
^ The TCM commands an immediate landing to 2nd gear.
^ The TCM inhibits TCC engagement.
^ The TCM turns off power to all the solenoids.
^ The TCM freezes transmission adaptive functions.
^ The ECM records the operating conditions when the Conditions for Setting the DTC are met. The ECM stores this information as Freeze Frame and Failure Records.
^ The TCM records the operating conditions when the Conditions for Setting the DTC are met. The TCM stores this information as Failure Records.
^ The TCM stores DTC P0562 in TCM history.

Conditions for Clearing the MIL/DTC
^ The ECM turns OFF the MIL after the third consecutive drive trip in which the TCM does not send a MIL illumination request.
^ A scan tool can clear the MIL/DTC.
^ The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without an emission related diagnostic fault occurring.
^ The TCM cancels the DTC default actions when the ignition switch is OFF long enough in order to power down the TCM.

Diagnostic Aids
Inspect for the following conditions:
^ Loose or damaged terminals at the generator
^ Loose or worn generator drive belt

Test Description








The numbers below refer to the step numbers on the diagnostic table.
4. This step tests the charging system voltage with a nominal load.
5. This step obtains the ignition voltage measurement reported by the TCM.
6. This step tests the voltage drop from the battery and ignition voltage input at the TCM.
10. This step tests the voltage drop from the ground terminals of the TCM to the ground terminal of the battery.