DTC 46

DTC 46 Rear Axle Channel Will Not Move:

CIRCUIT DESCRIPTION
This DTC is designed to detect bound-up ESB, a stuck motor, or a seized hydraulic modulator. When the release is commanded during initialization, the ESB 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 A046 can be set during normal operation. 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 cannot 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 insures that proper motor circuits are located in the proper connector cavities.
2. This step checks for proper motor movement during apply and release commands from the Tech 1.
3. This step compares EBCM command current to motor feedback current.
4. This step checks for proper hydraulic modulator gear and piston movement.
5. This step verifies that the motor can actually apply when commanded.
6. This test determines if the malfunction is caused by a defective EBCM or by a short circuit.

DIAGNOSTIC AIDS
A "Intermittent" malfunction in this DTC may result from a mechanical part of the system that sticks or binds.

The frequency of the malfunction can be checked by using the enhanced diagnostic function of the Tech 1.

DTC A046 may set after modulator disassembly if the modulator pistons are positioned at the bottom of their bore.

Depending on the frequency of the malfunction, a physical inspection of the mechanical parts suspected may be necessary.

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.