For 1990-2009 cars
ABS Components
Antilock Brake System Schematics
Handling ESD Sensitive Parts Notice

### Circuit Description

The ABS ACTIVE indicator lamp is connected to the IG COIL fuse. This circuit is hot in ON and START ignition switch positions. The Electronic Brake Control Module (EBCM) turns ON the ABS ACTIVE by grounding the ABS active indicator control circuit.

When the ignition switch is turned to the ON position, the EBCM turns ON the ABS ACTIVE indicator for 3 seconds for a bulb check. Whenever the vehicle is involved in an ABS event, the EBCM tuns ON the ABS ACTIVE indicator for the duration of the event (and 1-2 seconds after the event), notifying the driver that ABS is in operation.

### Diagnostic Aids

The following conditions may cause a malfunction:

• | A poor connection

• | Rubbed-through wire insulation

• | A broken wire inside the insulation

• | Open IG COIL fuse

• | Open bulb filament

• | Open within I/P gage printed circuit

Use the Lamp Test function of the Scan Tool in order to turn the indicator on while looking for an intermittent malfunction in the ABS warning indicator circuitry.

Thoroughly inspect any circuitry that may cause the intermittent 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

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
Important: Zero the J 39200 test leads before making any resistance measurements. Refer to the J 39200 user's manual.
1 | Was the ABS Diagnostic System Check performed? | -- | Go to Step 2 | Go to Diagnostic System Check - ABS
2 |

1. Turn the ignition switch to the OFF position.
2. Install a Scan Tool .
3. Turn the ignition switch to the ON position.

Do not start the engine.

4. Select Special Functions on the Scan Tool .
5. Select Lamp Test on the Scan Tool .
6. Use the Scan Tool in order to turn the amber ABS Active Indicator ON.

Did the amber ABS Active Indicator turn ON?

--

Go to Step 16

Go to Step 3

3 | Remove and inspect the IG COIL fuse. Is the IG COIL fuse open? | -- | Go to Step 4 | Go to Step 5
4 | Inspect the BLK/WHT wire between the Junction Block and the Instrument Panel Cluster (IPC) for damage that may cause a short to ground. Is there any damage present? | -- | Go to Step 10 | Go to Step 11
5 |

1. Turn the ignition switch to the ON position.
2. Use the J 39200 in order to measure the voltage between the IG COIL fuse terminal and ground.

Is the voltage within the specified range?

Battery Voltage

Go to Step 6

Go to Power Distribution Schematics in Wiring Systems

6 |

1. Reinstall the IG COIL fuse.
2. Disconnect the EBCM connector C1.
3. Turn the ignition switch to the ON position.
4. Connect a fused jumper wire between the EBCM connector C1 terminal A6 and ground.

Did the ABS Active Indicator lamp turn ON?

--

Go to Step 12

Go to Step 7

7 |

1. Disconnect the IPC connector C1.
2. Turn the ignition switch to the ON position.
3. Use the J 39200 in order to measure the voltage between the IPC connector C1 terminal 2 and ground.

Is the voltage within the specified range?

Battery Voltage

Go to Step 8

Go to Step 13

8 | Use the J 39200 in order to measure the resistance between the IPC connector C1 terminal 10 and the EBCM connector C1 terminal A6. Is the resistance within the specified range? | 0-2 ohms | Go to Step 9 | Go to Step 14
9 | Remove and inspect the ABS Active Indicator bulb. Refer to Instrument Cluster Bulb Replacement in Instrument Panel, Gauges and Console. Is the ABS Active Indicator bulb open? | -- | Go to Step 15 | Go to Step 16
10 |

1. Repair the short to ground in the BLK/WHT wire between the Junction Block and the IPC. Refer to Wiring Repairs in Wiring Systems.
2. Replace the IG COIL fuse.

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

11 | Replace the IG COIL fuse. Is the repair complete? | -- | Go to Diagnostic System Check - ABS | --
12 | Replace the EBCM. Refer to Electronic Brake Control Module Replacement . Is the repair complete? | -- | Go to Diagnostic System Check - ABS | --
13 | Repair the open or high resistance in the BLK/WHT wire between the Junction Block and the IPC. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check - ABS | --
14 | Repair the open or high resistance in the BLU/YEL wire between the IPC and the EBCM. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check - ABS | --
15 | Replace the ABS Active Indicator bulb. Refer to Instrument Cluster Bulb Replacement in Instrument Panel, Gauges and Console. Is the repair complete? | -- | Go to Diagnostic System Check - ABS | --
16 | The malfunction is intermittent or not present at this time. Refer to Diagnostic Aids for more information. Is the action complete? | -- | System OK | --