GM Service Manual Online
For 1990-2009 cars only

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P2533

Conditions for Running the DTC

    • Emergency mode is OFF.
    • No failure condition of CAN BUS failure.
    • No detection of Lost communication with ECM.
    • No detection of engine RPM failure.
    • Engine speed is more than 400 RPM.
    • No detection of system voltage low.
    • Ignition voltage is more than 9 volts.

Conditions for Setting the DTC

TCM detects ignition input OFF for 20 seconds.

Action Taken When the DTC Sets

    • TCM will request the illumination of MIL.
    • TCM records the operating condition when the Conditions for Setting the DTC are met. TCM stores this information as Failure Record.
    • TCM stores DTC in TCM history.
    • TCM turns Emergency mode ON.
        When the Emergency mode is ON, the following conditions occur:
       - The transmission will operate in 4th gear when the transmission is shifted into D, M+ or 4th range.
       - The transmission will operate in 2nd gear when the transmission is shifted into 2 or M- range.
       - Learn control is disabled.
       - Lock up control is disabled.
       - Adaptive control is disabled.
       - N-D shifting is disabled.
       - ABS function is disabled.

Conditions for Clearing the MIL/DTC

    • The MIL turns OFF when no failure is detected for three consecutive driving cycles.
    • The scan tool can clear the DTC from the TCM history.
    • TCM clears the DTC from the TCM history memory after forty consecutive warm-up cycles without fault.

Cause of Failure

TCM wiring harness and connectors

    •  Battery
    • TCM

Step

Action

Values

Yes

No

1

  1. Turn the ignition OFF.
  2. Install the Scan tool.
  3. Turn the ignition ON, with the engine OFF.
  4. Run the engine to 400 RPM or greater.
  5. Record then clear DTC(s).
  6. Select system voltage on the scan tool.
  7. Drive the vehicle and observe the scan tool.

Is the voltage within the values shown?

9-16V

Go to Step 4

Go to Step 2

2

    Caution: Refer to Battery Disconnect Caution in the Preface section.

  1. Disconnect the battery cable.
  2. Measure the battery voltage.

Is the voltage within the values shown?

9-16V

Go to Step 4

Go to Step 3

3

Replace the battery.

Is the replacement completed?

--

System OK

--

4

  1. Turn the headlamp ON.
  2. Turn the air conditioner ON.
  3. Run the engine to 400 RPM or greater.
  4. Observe the scan tool for system voltage.

Is the voltage within the values shown?

9-16V

Go to Step 6

Go to Step 5

5

  1. Turn the ignition LOCK.
  2. Repair the alternator circuit if necessary.

Is the action completed?

--

System OK

--

6

Inspect the Ef32, Ef30, F29 fuse for an open.

Was a problem found?

--

Go to Step 7

Go to Step 8

7

  1. Inspect the Ef32, Ef30, F29 fuse for short.
  2. Replace the fuse if necessary.

Is the replacement complete?

--

System OK

--

8

  1. Turn the ignition ON.
  2. Measure the voltage of Ef32, Ef30, F29.

Is the voltage within the values shown?

9-V

Go to Step 10

Go to Step 9

9

Repair the fuse voltage supply lines for open.

Is the action completed?

--

System OK

--

10

  1. Turn the ignition LOCK.
  2. Disconnect the TCM wiring connector.
  3. Measure the resistance between Ef30 fuse and terminal 6 of the TCM wiring connector J1.
  4. Measure the resistance between Ef20 fuse and terminal 22 of the TCM wiring connector J2.

Is the resistance within the values shown?

0 ohms

Go to Step 12

Go to Step 11

11

    • Repair the circuit (between Ef32 and terminal 6 of connector J1) for short to ground and open.
    • Repair the circuit (between Ef20 and terminal 22 of connector J2) for short to ground and open.

Is the repair completed?

--

System OK

--

12

  1. Disconnect the X201 connector and TCM connector.
  2. Turn the ignition ON.
  3. Measure the voltage of the terminal 22 of connector J2.

Is the voltage within the values shown?

9-16V

Go to Step 13

Go to Step 14

13

Repair the circuit from Ef20 to terminal 22 of the TCM connector J2 for short to battery.

Is the repair complete?

--

System OK

--

14

  1. Turn the ignition LOCK.
  2. Measure the resistance between F29 fuse and terminal 21 of the TCM wiring connector J2.

Is the resistance within the values shown?

0 ohms

Go to Step 17

Go to Step 15

15

Repair the circuit (between F29 and terminal 21 of connector J2) for short to ground and open.

Is the repair complete?

--

System OK

--

16

  1. Turn the ignition ON.
  2. Measure the voltage of the terminal 21 of connector J2.

Is the voltage within the values shown?

9-16V

Go to Step 17

Go to Step 18

17

Repair the circuit (between F29 and terminal 21 of connector J2) for short to battery.

Is the repair complete?

--

System OK

--

18

  1. Inspect the transaxle wiring for poor electrical connectors at the transaxle connector.
  2. Look for possible bent, backed out, deformed, or damaged terminals.
  3. Check for week terminal tension.

Was a condition found?

--

Verify repair and Go to Step 20

--

19

Replace the TCM.

Is the replacement complete?

--

Go to Step 20

--

20

  1. After the repair, use a scan tool "clear info" function and road test the vehicle.
  2. Review the "DTC info".

Has the last test failed or is the current DTC displayed?

--

Begin diagnosis again.

Repair verified Exit DTC chart.