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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1999 🢒 Chevy P32 RV/Van Chassis 🢒 DTC 🢒 DTC C0235 or C035 Rear Wheel Speed Signal Circuit Open

DTC C0235 or C035 Rear Wheel Speed Signal Circuit Open P32


Object Number: 191492 Size: MF
ABS Components P32
Antilock Brake System Schematics P32

Circuit Description

The EBCM receives the rear wheel speed signal from the Vehicle Control Module (VCM) for gas engine vehicles or the Vehicle Speed Sensor Buffer for diesel engine vehicles. The rear wheel speed signal originates from the Vehicle Speed Sensor (VSS) which is connected to the VCM (gas) or Vehicle Speed Sensor Buffer (diesel). When the vehicle is not moving, the VCM (gas) or Vehicle Speed Sensor Buffer (diesel) will have 12 VDC present on the circuit. The EBCM checks for this votage when the vehicle is not moving.

Conditions for Setting the DTC

EBCM not seeing the correct voltage level from the VCM (gas) or the Vehicle Speed Sensor Buffer (diesel) at startup.

Action Taken When the DTC Sets
    • The ABS indicator lamp turns on
    • The ABS disables

DTC C0235 is a Conition Latched DTC, which indicates that the above actions are true until the condition is cleared.

Conditions for Clearing the DTC
    • Repair the conditions responsible for setting the DTC
    • Use the Scan Tool Clear DTCs function

Diagnostic Aids

This DTC can be set by a faulty EBCM or a fault in CKT 696.

If the voltage readings are low or varying, the battery or charging system could be the cause. Check these areas before replacing any components. In addition, any of the following conditions may cause an intermittent malfunction:

    • A poor connection
    • Wire insulation that is rubbed through
    • A wire breaks inside the insulation

Thoroughly check any circuitry that is suspected of causing the intermittent complaint for the following conditions:

    • Backed out terminals
    • Improper mating
    • Broken locks
    • Improperly formed or damaged terminals
    • Poor terminal to wiring connections
    • Physical damage to the wiring harness

Test Description

The numbers below refer to the steps in the diagnostic table:

  1. This step uses the voltage output from the VCM (gas) or Vehicle Speed Sensor Buffer (diesel) to check CKT 1827 .

    2.

  2. This step checks the CKT 1827 for proper resistance.

    3.

  3. This step checks for a short in the wiring between the ECBM and the PCM.

Step

Action

Value(s)

Yes

No

1

Was the Diagnostic System Check performed?

--

Go to Step 2

Go to Diagnostic System Check - ABS

2

  1. Turn the ignition to OFF.
  2. Disconnect the 10-way EBCM harness connector from the EBCM.
  3. Turn the ignition to RUN.
  4. Using a J 39200 , measure the voltage at terminal E of the 10-way EBCM harness connector.

Is the voltage measurement within the specified range?

10-15 V

Go to Step 4

Go to Step 3

3

  1. Turn the ignition to OFF.
  2. Disconnect the VCM harness connector C1 for gas vehicles or the Vehicle Speed Sensor Buffer harness connector for diesel vehicles.
  3. Using a J 39200 , measure the resistance between the EBCM 10-way connector terminal E and the VCM harness connector C1 terminal 15 for gas vehicles or the Vehicle Speed Sensor Buffer harness connector terminal 10 for diesel vehicles.

Is the resistance measurement within the specified range?

0-2 ohms

Go to Step 5

Go to Step 8

4
  1. Turn the ignition to OFF.
  2. Reconnect all connectors.
  3. Turn the ignition to RUN.
  4. Using a Scan Tool , clear DTCs.
  5. Test drive the vehicle above 24 km/h (15 mph).
  6. Use a Scan Tool to read DTCs.

Did a DTC set?

--

Go to Step 6

Go to Step 7

5

Using the J 39200 , measure the resistance between the EBCM 10-way connector terminal E and ground.

Is the resistance measurement within the specified range?

OL

Go to Engine Controls for Vehicle Speed Sensor Diagnosis

Go to Step 9

6

Replace the EBCM. Refer to Electronic Brake Control Module Replacement .

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

7

Malfunction is intermittent, perform the following:

  1. Inspect all connectors and harnesses for damage which may result in high resistance when all components are connected.
  2. Refer to Diagnostic Aids for more information.
  3. Perform all necessary repairs.

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

8

Repair the open in CKT 696. Refer to Wiring Repairs .

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

9

Repair short to ground in CKT 696. Refer to Wiring Repairs .

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

DTC C0235 or C035 Rear Wheel Speed Signal Circuit Open P42


Object Number: 396489 Size: MF
ABS Components P42
Antilock Brake System Schematics P42

Circuit Description

The EBCM receives the rear wheel speed signal from the Vehicle Control Module (VCM) for gas engine vehicles or the Vehicle Speed Sensor Buffer for diesel engine vehicles. The rear wheel speed signal originates from the Vehicle Speed Sensor (VSS) which is connected to the VCM (gas) or Vehicle Speed Sensor Buffer (diesel). When the vehicle is not moving, the VCM (gas) or Vehicle Speed Sensor Buffer (diesel) will have 12 VDC present on the circuit. The EBCM checks for this votage when the vehicle is not moving.

Conditions for Setting the DTC

EBCM not seeing the correct voltage level from the VCM (gas) or the Vehicle Speed Sensor Buffer (diesel) at startup.

Action Taken When the DTC Sets
    • The ABS indicator lamp turns on
    • The ABS disables

DTC C0235 is a Conition Latched DTC, which indicates that the above actions are true until the condition is cleared.

Conditions for Clearing the DTC
    • Repair the conditions responsible for setting the DTC
    • Use the Scan Tool Clear DTCs function

Diagnostic Aids

This DTC can be set by a faulty EBCM or a fault in CKT 696.

If the voltage readings are low or varying, the battery or charging system could be the cause. Check these areas before replacing any components. In addition, any of the following conditions may cause an intermittent malfunction:

    • A poor connection
    • Wire insulation that is rubbed through
    • A wire breaks inside the insulation

Thoroughly check any circuitry that is suspected of causing the intermittent complaint for the following conditions:

    • Backed out terminals
    • Improper mating
    • Broken locks
    • Improperly formed or damaged terminals
    • Poor terminal to wiring connections
    • Physical damage to the wiring harness

Test Description

The numbers below refer to the steps in the diagnostic table:

  1. This step uses the voltage output from the VCM (gas) or Vehicle Speed Sensor Buffer (diesel) to check CKT 1827 .

    2.

  2. This step checks the CKT 1827 for proper resistance.

    3.

  3. This step checks for a short in the wiring between the ECBM and the PCM.

Step

Action

Value(s)

Yes

No

1

Was the Diagnostic System Check performed?

--

Go to Step 2

Go to Diagnostic System Check - ABS

2

  1. Turn the ignition to OFF.
  2. Disconnect the 10-way EBCM harness connector from the EBCM.
  3. Turn the ignition to RUN.
  4. Using a J 39200 , measure the voltage at terminal E of the 10-way EBCM harness connector.

Is the voltage measurement within the specified range?

10-15 V

Go to Step 4

Go to Step 3

3

  1. Turn the ignition to OFF.
  2. Disconnect the VCM harness connector C1 for gas vehicles or the Vehicle Speed Sensor Buffer harness connector for diesel vehicles.
  3. Using a J 39200 , measure the resistance between the EBCM 10-way connector terminal E and the VCM harness connector C1 terminal 15 for gas vehicles or the Vehicle Speed Sensor Buffer harness connector terminal 10 for diesel vehicles.

Is the resistance measurement within the specified range?

0-2 ohms

Go to Step 5

Go to Step 8

4
  1. Turn the ignition to OFF.
  2. Reconnect all connectors.
  3. Turn the ignition to RUN.
  4. Using a Scan Tool , clear DTCs.
  5. Test drive the vehicle above 24 km/h (15 mph).
  6. Use a Scan Tool to read DTCs.

Did a DTC set?

--

Go to Step 6

Go to Step 7

5

Using the J 39200 , measure the resistance between the EBCM 10-way connector terminal E and ground.

Is the resistance measurement within the specified range?

OL

Go to Engine Controls

Go to Step 9

6

Replace the EBCM. Refer to Electronic Brake Control Module Replacement .

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

7

Malfunction is intermittent, perform the following:

  1. Inspect all connectors and harnesses for damage which may result in high resistance when all components are connected.
  2. Refer to Diagnostic Aids for more information.
  3. Perform all necessary repairs.

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

8

Repair the open in CKT 696. Refer to Wiring Repairs .

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

9

Repair short to ground in CKT 696. Refer to Wiring Repairs .

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--