For 1990-2009 cars

### Circuit Description

The TC indicator is controlled by the EBCM. The EBCM supplies the ground to the TC indicator circuit to turn the indicator on. When the TC indicator circuit is not grounded at the EBCM, the TC indicator remains off. When the EBCM sees the traction control switch voltage go low, it turns the TC indicator on and disables traction control. The EBCM harness connector contains a shorting bar for the TC indicator circuit. When the EBCM connector is disconnected from the EBCM, the shorting bar shorts the TC indicator terminal to ground turning on the indicator.

### Diagnostic Aids

If the EBCM harness connector is not securely connected to the EBCM, the shorting bar in the harness connector may turn on the TC indicator. Make sure the EBCM harness connector is securely connected to the EBCM.

• | It is very important that a thorough inspection of the wiring and connectors be performed. Failure to carefully and fully inspect wiring and connectors may result in misdiagnosis, causing part replacement with reappearance of the malfunction.

• | Thoroughly inspect any circuitry that may be causing the complaint for the following conditions:

- | Backed out terminals

- | Improper mating

- | Broken locks

- | Improperly formed or damaged terminals

- | Poor terminal-to-wiring connections

- | Physical damage to the wiring harness

• | The following conditions may cause an intermittent malfunction:

- | A poor connection

- | Rubbed-through wire insulation

- | A broken wire inside the insulation

• | If an intermittent malfunction exists refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems for further diagnosis.

### Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

1. If there is a malfunction in the Engine Control Module or Transmission Control Module that is inhibiting Traction Control, the TC indicator will turn on, but will not have a DTC stored in the EBCM. The engine or transmission DTCs must be repaired before further diagnosis of the TC indicator circuit.

2. This step checks for an internal EBCM malfunction. You must install the pinout box and cable adapter to the harness connector at this point to prevent the shorting bar in the harness connector from grounding the circuit and turning on the indicator.

3. This step checks for a short to ground in the TC Indicator Control circuit.

#### Traction Control Indicator Always On No DTC

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
Schematic Reference: Antilock Brake System Schematics
1 | Did you perform the Diagnostic System Check ? | -- | Go to Step 2 | Go to Diagnostic System Check - ABS
2 |

1. Turn the ignition switch to the ON position, engine off.
2. Using a scan tool, select the Display DTC function for Engine and Transmission.

Are there any DTCs set in Engine or Transmission?

--

Go to Diagnostic Trouble Code (DTC) List in Engine Controls

Go to Step 3

3 |

1. Turn the ignition switch to the ON position, engine off.
2. Using a scan tool enter ABS/TCS Data List.
3. While monitoring the TCS Switch State, press and hold the TCS On/Off switch for three seconds, then release the TCS On/Off switch.

Does the switch state change from Off to On as the TCS switch is pressed and released?

--

Go to Step 4

Go to Step 9

4 |

1. Turn the ignition switch to the OFF position.
2. Disconnect the EBCM connector C1.
3. Install the J 39700 Universal Pinout Box using the J 39700-280 Cable Adapter to connector C1 only.
4. Turn the ignition switch to the ON position, engine off.

Does the TC Indicator turn off?

--

Go to Step 5

Go to Step 6

5 | Replace the EBCM. Refer to Electronic Brake Control Module Replacement . Is the replacement complete? | -- | Go to Diagnostic System Check - ABS | --
6 |

1. Turn the ignition switch to the OFF position.
2. Disconnect the Instrument Cluster connector.
3. Using DMM, measure the resistance between terminals 20 and 19 of J 39700 .

Is the resistance within the range specified in the value(s) column?

OL (infinite)

Go to Step 8

Go to Step 7

7 | Repair the TC Indicator Control circuit for a short to ground. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check - ABS | --
8 | Important: Reprogram the instrument cluster. Refer to Instrument Cluster Programming/Synchronization in Instrument Panel, Gauges and Console. Replace the Instrument Cluster. Refer to Instrument Cluster Replacement in Instrument Panel, Gauges and Console.

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

9 |

1. Turn the ignition switch to the OFF position.
2. Disconnect the EBTCM connector C1.
3. Install the J 39700 Universal Pinout Box using the J 39700-280 Cable Adapter to connector C1 only.
4. Using DMM, measure the resistance between terminals 31 and 19 of J 39700 .

Is the resistance within the range specified in the value(s) column?

OL

Go to Step 5

Go to Step 10

10 | Repair Traction Control Switch Signal for an Short to Ground, being sure to check the traction control switch for a short. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check - ABS | --