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

### Circuit Description

Four-way serial communication is sent back and forth between the EBCM, IPC, PCM, and the BCM. A message from the IPC is sent to the BCM within seven seconds after ABS initialization. A serial communication failure does not allow the proper warning indicator commands to be sent back to the IPC.

### Diagnostic Aids

The ETS OFF indicator will be ON and the Enhanced Traction System will be disabled whenever the scan tool is connected to the DLC with the ignition switch is in the ON position.

Use the Lamp Test function of the Scan Tool in order to turn the indicator ON while looking for an intermittent malfunction in the ETS OFF 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

### Test Description

1. This test determines if a Powertrain malfunction has turned the ETS Off indicator ON.

2. This test determines if the malfunction is caused by the IPC.

3. This test checks for an ETS Off switch stuck in the closed position.

4. This test checks for a short to ground in the switched input to the BCM.

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. Connect a Scan Tool .
3. Turn the ignition switch to the ON position.
4. Use the Scan Tool in order to check for any PCM DTCs.

Are there any PCM DTCs?

--

Go to Powertrain On Board Diagnostic (OBD) System Check in Engine Controls

Go to Step 3

3 |

1. Use the Scan Tool to select the BODY Menu.
2. Use the Scan Tool to select IPC then Lamp Test.
3. Use the Scan Tool to turn the warning indicators OFF.

Did the warning indicators turn OFF?

--

Go to Step 4

Go to Diagnostic System Check - Instrument Cluster in Instrument Panel, Gages and Console

4 | Disconnect the ETS Off switch connector. Does the ETS Off indicator turn OFF? | -- | Go to Step 7 | Go to Step 5
5 |

1. Disconnect the BCM connector C3.
2. Using the J 39200 measure the resistance between the ETS Off switch harness connector terminal A and ground.

Is the resistance within the specified range?

OL

(Infinite)

Go to Step 6

Go to Step 8

6 |

1. Turn the ignition switch to the OFF position.
2. Inspect the following components:

• | The BCM connector C3

• | The ETS Off connector

3. Inspect the above components for the following conditions:

• | Damage

• | Poor terminal contact

• | Terminal corrosion

Are there signs of poor terminal contact, corrosion or damaged terminals?

--

Go to Step 9

Go to Step 10

7 | Replace the ETS Off switch. Is the repair complete? | -- | Go to Diagnostic System Check - ABS | --
8 | Repair short to ground in CKT 1571. Is the repair complete? | -- | Go to Diagnostic System Check - ABS | --
9 | Replace all of the terminals or connectors that exhibit signs of poor terminal contact, corrosion or damaged terminal(s). Is the repair complete? | -- | Go to Diagnostic System Check - ABS | --
10 | Replace the BCM. Is the repair complete? | -- | Go to Diagnostic System Check - ABS | --