GM Service Manual Online
For 1990-2009 cars only

DTC P0562 V6

DTC Description

This diagnostic procedure supports DTC P0562 System Voltage Low.

Circuit Description

The transmission control module (TCM) continuously monitors the system voltage on the battery (circuit 740) and ignition (circuit 339) circuits. Lower than normal voltage may be inadequate to operate the transmission control solenoids properly. Improper solenoid operation may cause erratic transmission operation and tie-up conditions, which may result in internal damage.

When the TCM detects low voltage, DTC P0562 sets. DTC P0562 is a type C DTC.

Automatic Transmission Controls Schematics , Automatic Transmission Inline 20-Way Connector End View , Automatic Transmission Internal Connector End Views , Automatic Transmission Control Module Connector End Views , and Automatic Transmission Related Connector End Views to aid in diagnosis.

Conditions for Running the DTC

The engine speed is greater than 1,200 RPM.

Conditions for Setting the DTC

The TCM detects system voltage less than 11 V for 10 seconds.

Action Taken When the DTC Sets

    • The TCM does not request the engine control (ECM) to illuminate the check powertrain icon.
    • The TCM records the operating conditions when the conditions for setting the DTC are met. The TCM records this information as a Failure Record.
    • The TCM stores DTC P0562 in TCM history.

Conditions for Clearing the DTC

    • The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without a non-emission related diagnostic fault occurring.
    • Tech 2 can clear the DTC.

Diagnostic Aids

    • Observe the instrument cluster's multi-function display messaging that would indicate the electrical system requires service.
    • Inspect for the following conditions:
       - Loose or damaged terminals at the generator, and
       - Loose or worn generator drive belt.

Test Description

The following numbers refer to the step numbers in the diagnostic table:

3 The alternator warning indicator will illuminate if there is a problem with the charging system of the vehicle.

4 Checks the charging system voltage with a nominal load.

5 Checks if the ignition voltage measurement reported by the TCM is within acceptable parameters.

7 Checks if there is battery voltage supplied to the TCM.

8 Checks if there is battery voltage supplied through the ignition circuit to the TCM.

9 Checks the ground circuits of the TCM.

Step

Action

Yes

No

1

Has the Diagnostic System Check been performed?

Go to Step 3

Check the serviceability of the battery, refer to Battery Inspection/Test

2

  1. Connect Tech 2 to the DLC.
  2. Turn on the ignition, with the engine off.
  3. Important: Before clearing the DTC, use the Tech 2 Freeze Frame/Failure Record in order to record the transmission parameters at the time the DTC set. Using Tech 2 to clear the DTC(s) erases the Freeze Frame/Failure Record records from the TCM.

  4. On Tech 2 select: Transmission/Automatic Transmission/Diagnostic Trouble Codes/Freeze Frame.
  5. Select the relevant DTC and note the parameters at the time of the DTC setting.
  6. On Tech 2 select: Diagnostic Trouble Codes/Clear Engine and Transmission DTCs.
  7. Follow the instructions on Tech 2 and clear the DTCs.
  8. Using a multimeter set to measure voltage, probe across the battery terminals.

Does the multimeter display greater than 11 V?

Go to Step 3

Check the serviceability of the battery, refer to Battery Inspection/Test

3

  1. Start the engine.
  2. Allow the engine to warm up to normal operating temperature.

Is the alternator fail warning indicator illuminated?

Refer to Battery Charging

Go to Step 4

4

  1. Turn on the high beam headlamps.
  2. Turn the HVAC fan control to the highest speed setting.
  3. Turn on the rear window demister.
  4. Increase the engine speed to 1,500 RPM.
  5. Using a multimeter set to measure voltage, probe across the battery terminals.

Does the multimeter display 12.5-14.5 V?

Go to Step 5

Refer to Charging System Inoperative

5

  1. Increase the engine speed to 1,500 RPM.
  2. On Tech 2 select: Data Display/Transmission Data

Does Tech 2 display the Ignition Voltage parameter within 12.5-14.5 V?

Check for an intermittent fault to the circuit, refer to Testing for Intermittent Conditions and Poor Connections

Go to Step 6

6

Check the fuses F8 and F29 for serviceability.

Are the fuses serviceable?

the

Go to Step 7

Replace the affected fuse(s). If fuse (s) blow again, check for a short to ground in the fuses circuit.

Go to Step 13

7

  1. Turn off the ignition.
  2. Disconnect the TCM connector A112-X1.
  3. Using a multimeter set to measure voltage, probe between connector A112-X1 pin 32 and a known ground.

Does the multimeter display battery voltage?

Go to Step 8

Check circuits 740 and 642 for an open, high resistance or short to ground.

Repair or replace the affected circuit

8

  1. Using a multimeter set to measure voltage, probe between connector A113-X1 pin 31 and a known ground.
  2. Turn on the ignition, with the engine off.

Does the multimeter display battery voltage?

Go to Step 9

Check circuits 3 and 339 for an open, high resistance or short to ground.

Repair or replace the affected circuit.

9

Using a multimeter set to measure resistance, probe between connector A112-X1 pin 49 and a known ground.

Does the multimeter display continuity?

Go to Step 10

Check circuit 451 for an open or high resistance

Repair or replace circuit 451

10

Replace the TCM, refer to Transmission Control Module Replacement.

Is the action completer?

Go to Step 11

-

11

Perform the following procedure in order to verify the repair:

  1. On Tech 2 select: Diagnostic Trouble Codes/Clear Engine and Transmission DTCs.
  2. Follow the instructions on Tech 2 and clear any DTCs.
  3. Operate the vehicle under the following conditions:
  4. • Start the engine.
    • Allow the engine to warm up to normal operating temperature.
    • Raise the engine speed to at least 1,200 RPM.
    • TCM voltage must be greater than 11 V for 12 seconds.
  5. On Tech 2 select:
  6. Diagnostic Trouble Codes/Read DTC Information.

Has DTC P0562 set?

Go to Step 2

Go to Step 12

12

On Tech 2 select: Diagnostic Trouble Codes/Read DTC Information.

Does Tech 2 display any DTCs you have not diagnosed?

Refer to Diagnostic Trouble Code (DTC) List/Type

System OK

When all diagnosis and repairs are completed, check the system for correct operation.