Circuit Description
The aim of the controller area network (CAN) network is to allow exchange of information between the engine control module (ECM) and the antilock brake system (ABS) module.
Conditions for Setting the DTC
| • | No message from the ECM module during 0.5 seconds |
| • | Ignition ON |
Action Taken When the DTC Sets
| • | The malfunction indicator lamp (MIL) will illuminate. |
| • | The ECM will record operating conditions at the time the diagnostic fails. This information will be stored in the freeze frame and failure records buffers. |
| • | A history diagnostic trouble code (DTC) is stored. |
Conditions for Clearing the MIL/DTC
| • | The MIL will turn OFF at the end of 3 consecutive ignition cycles in which the diagnostic runs without a fault. |
| • | A history DTC will clear after 40 warm-up cycles without a fault. |
| • | DTCs can be cleared by using the scan tool. |
Diagnostic Aids
An intermittent problem may be caused by a poor connection, rubbed through wire insulation, or wire that is broken inside the insulation.
Any circuitry that is suspected as causing the complaint should be thoroughly inspected for the following conditions:
| • | Backed-out terminals |
| • | Improper mating |
| • | Broken locks |
| • | Improperly formed |
| • | Damaged terminals |
| • | Poor terminals to wire connection |
| • | Physical damage to the wiring harness |
Step | Action | Yes | No |
|---|---|---|---|
1 | Did you perform the Diagnostic System Check-ABS? | Go to Step 2 | |
2 |
Are any diagnostic trouble codes (DTCs) displayed? | Go to Step 3 | System OK |
3 | Refer to the applicable DTC table. Start with the DTC with the lowest numerical value and move up. Is the DTC identified as valid trouble code C0075? | Go to Step 4 | System OK |
4 |
Is the problem found? | Go to Step 6 | Go to Step 5 |
5 | Inspect for an open or short to ground in the wire between the CAN low of the ABS module and the ECM connector terminal. Is the problem found? | Go to Step 6 | Go to Step 7 |
6 | Change the unshielded twisted pair between the ABS module and the ECM or repair the connector terminal as needed. Is the repair complete? | Go to Step 9 | -- |
7 | Replace the ABS module. Did you complete the replacement? | Go to Step 9 | -- |
8 | Replace the ECM. Refer to Engine Control Module Replacement in Engine Controls - 2.0L or Engine Control Module Replacement in Engine Control - 2.5L. Did you complete the replacement? | Go to Step 10 | -- |
9 |
Does the scan tool indicate this diagnostic has run and passed? | Go to Step 10 | Go to Step 2 |
10 | Check if any additional DTCs are set. Are any DTCs displayed that have not been diagnosed? | System OK |
