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DTC 36

DTC 36 Low System Voltage (Part 1 Of 2):




DTC 36 Low System Voltage (Part 2 Of 2):




DTC 36 Low System Voltage:







Circuit Description:
This DTC is used to monitor the voltage level available to the EBCM controller. If the voltage drops below 11 volts, full performance of the ABS system cannot be guaranteed. During ABS operation, there are several current requirements that will cause battery voltage to drop. Because of this, voltage is monitored prior to ABS to indicate good charging system condition and also during ABS when voltage may drop significantly.

DTC Will Set When:
DTC 36 can only be set if the vehicle's speed is greater than 5 km/h (3 mph). If the switched battery voltage is less than 11.2 volts non-ABS or less than 9.6 volts ABS, a malfunction exists.

Action Taken:
A malfunction DTC is stored, ABS is disabled and the ABS warning lamp is turned "ON."

DTC Chart Test Description:
Number(s) below refer to circled number(s) on the diagnostic chart.
1. Checks to see what voltage is readily available at terminal "D" of the EBCM. If voltage is representative of good charging system condition, a malfunction is not present.
2. Isolates the condition to high circuit resistance, or improper charging system operation.
3. Isolates which circuit is the source of the high resistance condition.
4. Checks for high resistance in CKTs 542 or 2.
5. Checks for high resistance in CKT 341.
6. Checks for high resistance in the ignition fuse feed circuit.
7. Checks for possible intermittent malfunction or a malfunctioning 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 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.

While performing a voltage load test, if it is noted that only ignition voltage drops below acceptable voltage levels, CKT 341 should be checked for high resistance or an open condition.