GM Service Manual Online
For 1990-2009 cars only

Object Number: 155214  Size: SF
ABS Components
Antilock Brake System Schematics

Circuit Description

DTC C1356 identifies a TCS motor that cannot energize due to an open in the motor circuitry.

Conditions for Setting the DTC

DTC C1356 can only set when the TCS motor is commanded off.

A malfunction exists if the EBCM/EBTCM detects an out of range voltage on either of the left front TCS motor circuits indicating an open circuit.

Action Taken When the DTC Sets

    • An open TCS motor will not activate when requested.
    • A malfunction DTC stores.
    • The TCS disables.
    • The amber TCS indicator turns on.

Conditions for Clearing the DTC

    • The condition responsible for setting the DTC no longer exists and the Scan Tool Clear DTC function is used.
    • 100 drive cycles pass with no DTC detected.

Diagnostic Aids

Use the enhanced diagnostic function of the Scan Tool in order to measure the frequency of the malfunction. Refer to the Scan Tool manual or Scan Tool Diagnostics located in this section for the procedure.

If the malfunction is not current perform the following procedure in order to pinpoint an intermittent malfunction in the motor circuitry or connections:

  1. Wiggle the wires of the affected channel.
  2. Inspect to see if the DTC resets.

Thoroughly inspect any circuitry that may cause the intermittent complaint for the following conditions:

    • Rubbed-through wire insulation
    • A broken wire inside the insulation
    • Backed out terminals
    • Improper mating
    • Broken locks
    • Improperly formed or damaged terminals
    • Poor terminal-to-wiring connections
    • Physical damage to the wiring harness

Important: Zero the J 39200 test leads before making any resistance measurements.

Step

Action

Value(s)

Yes

No

1

Was the Diagnostic System Check performed?

--

Go to Step 2

Go to Diagnostic System Check - ABS

2

Does DTC C1356 occur intermittently?

--

Go to Diagnostic Aids

Go to Step 3

3

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the 4-way TCS motor pack connector.
  3. Use the J 39200 in order to measure the resistance between the 4-way TCS motor pack connector terminal A and the 4-way TCS motor pack connector terminal B.

Is the resistance within the specified range?

0.2-1.5 ohms

Go to Step 4

Go to Step 8

4

  1. Disconnect the 8-way EBCM/EBTCM connector C3.
  2. Use J 39200 in order to measure the resistance between the 4-way TCS motor pack harness connector terminal A and the 8-way EBCM/EBTCM harness connector C3 terminal H.

Is the resistance within the specified range?

0.0-2.0 ohms

Go to Step 5

Go to Step 9

5

Use the J 39200 in order to measure the resistance between the 4-way TCS motor pack connector terminal B and the 8-way EBCM/EBTCM harness connector C3 terminal G.

Is the resistance within the specified range?

0.0-2.0 ohms

Go to Step 6

Go to Step 10

6

  1. Inspect the 4-way TCS motor pack connector and the 4-way TCS motor pack harness connector for the following conditions:
  2. • Poor terminal contact
    • Terminal corrosion
    • Damaged terminals
  3. Inspect the 8-way EBCM/EBTCM connector C3 and the 8-way EBCM/EBTCM harness connector C3 for the following conditions:
  4. • Poor terminal contact
    • Terminal corrosion
    • Damaged terminals

Is there poor terminal contact, terminal corrosion, or terminal damage evident?

--

Go to Step 11

Go to Step 7

7

  1. Reconnect the 4-way TCS motor pack connector.
  2. Reconnect the 8-way EBCM/EBTCM connector C3.
  3. Start the vehicle.
  4. Test drive the vehicle obtaining a speed at least 16 km/h (10 mph).
  5. Stop the vehicle.
  6. Turn the ignition switch to the OFF position.
  7. Repeat the drive sequence two additional times.
  8. Use the scan tool in order to inspect for DTCs.

Did DTC C1356 set as a current DTC in the last three drive cycles?

--

Go to Step 12

Go to Step 13

8

Replace the TCS motor pack. Refer to Traction Control System Motor Pack Replacement .

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

9

Repair the open or the high resistance in CKT 564.

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

10

Repair the open or the high resistance in CKT 565.

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

11

Replace all of the terminals or the connectors that exhibit the following conditions:

    • Poor terminal contact
    • Terminal corrosion
    • Damaged terminals

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

12

Replace the EBCM/EBTCM. Refer to Electronic Brake and Traction Control Module Replacement .

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

13

The malfunction is intermittent or not present at this time?

Is a concern still present?

--

Go to Diagnostic Aids

Go to Diagnostic System Check - ABS