A098

DTC A098 Accelerometer Circuit Open Or Shorted Battery Or Ground:

Circuit Description:

The EBCM provides power (5 volts) and ground to the accelerometer through CKT 9Q01 and CKT 9RO1 respectively. The accelerometer converts the change in vehicle motion, or inertia, into a voltage signal. This signal is sent to the EBCM through CKT 9S01.

The accelerometer provides additional vehicle speed reference to the EBCM which is needed when the vehicle is in four-wheel-drive mode. The voltage signal ranges, from 2.5 volts at zero speed change (or constant motion), to about 0 volts under heavy acceleration, to near 5 volts under heavy braking.

Failure Condition:

DTC A098 can be set anytime when the EBCM detects a short to battery in accelerometer signal circuit.

Action Taken:

A DTC A098 is stored, ABS is disabled and the "ABS" indicator is turned on. If failure occurs during an ABS stop, ABS is disabled after the completion of the ABS cycle.

Test Description:

Number(s) below refer to circled number(s) on the diagnostic chart.
1. This step verifies whether the malfunction is currently present.
2. This step checks for a short to ground in accelerometer signal circuit.
3. This step checks for a short to voltage in accelerometer signal circuit.
4. This step checks for an open or high resistance in accelerometer signal circuit.
5. This step checks for a possible intermittent malfunction due to poor terminal contact.
6. This step checks for a faulty accelerometer or EBCM.

Diagnostic Aids:

An "intermittent" malfunction may be caused by a poor connection, rubbed through wire insulation or a wire that is broken inside the insulation.

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

Any circuitry that is suspected of 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.