A045
Circuit Description
Current is supplied to the EMB through terminal "B" of the three way motor pack connector. When a release of the EMB is commanded, the EBCM grounds the EMB input and allows the EMB to be energized to release the motor.
This DTC is designed to detect non-actuating EMB, stuck motor or a seized hydraulic modulator. When the release is commanded during initialization, the EMB should release the motor, resulting in sensed current being less than commanded current (motor is spinning freely). If the motor is not moving, sensed current will be equal to stall current.
Failure Condition
DTC A045 can be set at 5 km/h (3 mph). If the EBCM detects a condition in which it cannot move the motor in either direction, a malfunction exists.
Action Taken
This malfunction indicates the channel can not be moved properly. A malfunction DTC is stored, ABS is disabled and the ABS indicator lamp is turned "ON."
Test Description
Number(s) below refer to circled number(s) on the diagnostic chart.
1. This step ensures motor circuits are in the proper connector cavity.
2. This step checks for the motor movement during release.
3. This procedure compares feedback current to command current during apply.
4. This step checks to see if hydraulic modulator is functioning properly.
5. This step checks if motor can apply properly under load.
6. This step serves to isolate the malfunction to either the EBCM or a short between CKTs 1282 and 1283.
Diagnostic Aids
An "Intermittent" malfunction in this DTC may result from a mechanical part of the system that sticks, binds, or slips.
The frequency of the malfunction can be checked by using the enhanced diagnostic function of the Tech 1 as described in "Enhanced Diagnostics." DTC A045 may set after modulator disassembly if the modulator pistons are positioned at the bottom of their bore.
Any circuitry, that is suspected as causing the intermittent complaint, should be thoroughly checked for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, poor terminal to wiring connections or physical damage to the wiring harness.
Notice: This DTC may fail if low voltage (10 volts or less) was present when initialization occurred. Ensure battery/charging system is functioning properly.