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: |
| - | CKT 848 |
| - | CKT 849 |
| - | CKT 853 |
| - | CKT 1659 |
| • | DTC C1273 will also set if an open circuit exists in CKT 1451. |
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 are other possible causes of this malfunction: |
| - | The ABS/TCC 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 Diagnostic System Check performed? | -- | Go to Diagnostic System Check | |
2 |
Is the resistance less than the specified value? | 2 ohms | ||
3 |
Is the resistance equal to the specified value? | OL (Infinite) | ||
4 |
Is the resistance equal to the specified value? | OL (Infinite) | ||
5 |
Is the resistance within specifications? | OL (Infinite) | ||
6 | Measure the resistance between the J 38716 pinout box terminals 26 and 1. Is the resistance within specifications? | OL (Infinite) | ||
7 | Repair the open or high resistance in CKT 1451. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check | -- |
8 | Repair the short to ground in CKT 848. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check | -- |
9 | Repair the short to ground in CKT 849. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check | -- |
10 | Repair the short to ground in CKT 1659. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check | -- |
11 | Repair the short to ground in CKT 853. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check | -- |
12 | Replace the EBCM/EBTCM. Refer to Electronic Brake and Traction Control Module Replacement . Is the repair complete? | -- | Go to Diagnostic System Check | -- |
