Circuit Description
The BPMV fluid level switch alerts the EBCM/EBTCM to a condition of low brake fluid in the BPMV reservoir. The fluid level switch is located in the BPMV's reservoir.
When the reservoir contains sufficient fluid, the fluid level switch is normally closed. When the fluid level is low, the switch opens. The open switch causes the EBCM/EBTCM to turn on the ANTILOCK indicator.
Conditions for Setting the DTC
- The DTC C1273 sets when the EBCM/EBTCM detects a short to ground in the BPMV fluid level switch circuitry. The following list indicates possible locations of this short:
- DTC C1273 will also set if an open circuit exists in CKT 1451.
| • | CKT 848 |
| • | CKT 849 |
| • | CKT 853 |
| • | CKT 1659 |
Action Taken When the DTC Sets
The following actions are taken when the DTC sets:
| • | DTC C1273 is stored |
| • | The ABS is disabled |
| • | The ANTILOCK indicator lamp is turned on |
Conditions for Clearing the DTC
The DTC will clear under following conditions:
| • | Conditions for the malfunction are no longer present. Use the scan tool clear DTCs function. |
| • | 100 ignition switch key cycles have passed without detecting any malfunctions |
Diagnostic Aids
| • | The following conditions may be other possible causes of this malfunction: |
| - | The TCC/antilock switch circuit is shorted to ground |
| - | The BPMV fluid level switch circuit is shorted to ground |
| - | The ABS Pump Motor Pressure Switch circuit is shorted to ground |
| • | Perform a thorough inspection of the wiring and the connectors. |
| Failure to carefully inspect wiring may result in a misdiagnosis. A misdiagnosis may result in replacing parts without repairing the malfunction. |
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Was the ABS Diagnostic System Check performed? | -- | Go to Step 2 | |
2 |
Is the resistance less than the specified value? | 2 ohms | Go to Step 3 | Go to Step 7 |
3 |
Is the resistance within the specified range? | OL (Infinite) | Go to Step 4 | Go to Step 8 |
4 |
Is the resistance within the specified range? | OL (Infinite) | Go to Step 5 | Go to Step 9 |
5 |
Is the resistance within the specified range? | OL (Infinite) | Go to Step 6 | Go to Step 10 |
6 | Use the J 39200 in order to measure the resistance between the J 38716 pinout box terminal 26 and terminal 1. Is the resistance within the specified range? | OL (Infinite) | Go to Step 12 | Go to Step 11 |
7 | Repair the open or high resistance in CKT 1451. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | -- | |
8 | Repair the short to ground in CKT 848. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | -- | |
9 | Repair the short to ground in CKT 849. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | -- | |
10 | Repair the short to ground in CKT 1659. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | -- | |
11 | Repair the short to ground in CKT 853. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | -- | |
12 | Replace the EBCM/EBTCM. Refer to Electronic Brake and Traction Control Module Replacement . Is the repair complete? | -- | -- |
