Circuit Description
DTC C1277 identifies a solenoid that cannot be energized due to a short to voltage in the solenoid circuitry. The malfunction can affect ABS operation since the flow of brake fluid to the wheel cylinder cannot be stopped. The unstoppable flow of brake fluid to the wheel cylinder makes ABS operation for that channel impossible.
Conditions for Setting the DTC
| • | DTC C1277 can set only when the brake solenoid valve is commanded on. |
| • | A malfunction exists if the EBCM detects the left front brake solenoid valve control circuit voltage is not within specifications. |
Action Taken When the DTC Sets
| • | A malfunction DTC stores. |
| • | The ABS disables. |
| • | The ABS warning indicator turns ON. |
Conditions for Clearing the DTC
| • | The condition responsible for setting the DTC no longer exists and the Scan Tool Clear DTCs function is used. |
| • | 100 drive cycles pass with no DTCs detected. A drive cycle consists of starting the vehicle, driving the vehicle over 16 km/h (10 mph), stopping and then turning the ignition OFF. |
Diagnostic Aids
Use the enhanced diagnostic function of the Scan Tool in order to measure the frequency of the malfunction.
Any circuitry that is suspected of causing the intermittent complaint should be thoroughly checked for improper mating, improperly formed or damaged terminals, poor terminal to wiring connections, or physical damage to the wiring harness.
Test Description
-
This test checks for a short to voltage in the solenoid circuit.
-
This test checks the solenoid for the proper resistance value.
-
This test determines if the malfunction is caused by the EBCM.
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. Important: Difficulty may occur when trying to locate the intermittent malfunctions in the wheel speed sensor circuit. Do not disturb any of the electrical connections. Change electrical connections only when instructed to do so by a step in the diagnostic table. Changing the electrical connections at the correct time will ensure that an intermittent electrical connection will not be corrected until the source of the malfunction is found. | ||||
1 | Was A Diagnostic System Check-ABS performed? | -- | ||
Is the voltage within the specified range? | 0-1 V | |||
Is the resistance within the specified range? | 2.5-5.0 ohms | |||
Did DTC C1277 set during the past three ignition cycles? | -- | |||
5 | Repair the short to voltage in the BLU/WHT wire between the EBCM and the LF ABS solenoid. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | -- | |
6 | Replace the LF ABS solenoid. Refer to Brake Solenoid Valve Replacement . Is the repair complete? | -- | -- | |
7 | Replace the EBCM. Refer to Electronic Brake Control Module Replacement . Is the repair complete? | -- | -- | |
