For 1990-2009 cars

### Diagnostic Aids

An inoperative LED on the EBCM may cause the EBCM to illuminate an invalid combination of LEDs. This does not, however, indicate that the EBCM is non-functional or needs to be replaced. You may be able to navigate to the correct diagnostic procedure by determining which LED is inoperative and combining the displayed LEDs with an inoperative LED in order to create a valid diagnostic fault display.

For example:

• | The EBCM displays illuminated LFT and FRT LEDs.

• | A technician finds that the MOD LED is inoperative.

A safe assumption to make is that the EBCM is indicating a left, front modulator diagnostic fault.

If using the specified procedure does not indicate a valid fault, or if more than one LED is found to be inoperative, the EBCM may need to be replaced.

Step | Action | Yes | No
--- | --- | --- | ---
1 | Did you perform the Air ABS Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Air ABS
2 |

1. Turn ON the ignition.
2. Perform the magnetic reset procedure. Refer to Status Lamp Resetting .

Do all the LEDs on the EBCM illuminate during the reset procedure?

Go to Step 3

Go to Diagnostic Aids

3 | Important: Following EBCM replacement, perform the EBCM self-configuration procedure. Replace the EBCM. Refer to Electronic Brake Control Module Replacement . Did you complete the replacement? | Go to Step 4 | --
4 |

1. Turn ON the ignition.
2. Observe the LEDs on the EBCM after the ignition has been ON for 10 seconds.

Does the EBCM display only an illuminated green VLT LED?

System OK

Go to Diagnostic System Check - Air ABS