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For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 1998 🢒 Firebird 🢒 DTC 🢒 DTC C0239 TCS Spark Retard Monitoring Malfunction

Object Number: 415667 Size: MF

Circuit Description

Spark Retard is simultaneously controlled by the EBTCM and the PCM. The PCM supplies a 12 volt pull up voltage. This voltage is monitored by the PCM, the EBTCM requests spark retard by pulling the voltage low.

Conditions for Setting the DTC

DTC C0239 can be set anytime when the EBTCM senses a short to ground, a short to battery voltage , or an open in CKT 1687.

Action Taken When the DTC Sets
    • A malfunction DTC is stored.
    • The ABS/TCS is disabled.
    • The Red BRAKE Warning indicator turn on.

Conditions for Clearing the DTC
    • Condition for DTC is no longer present and scan tool clear DTC function is used.
    • 100 ignition cycles have passed with no DTC(s) detected.

Diagnostic Aids
    • It is very important that a thorough inspection of the wiring and connectors be performed. Failure to carefully and fully inspect wiring and connectors may result in misdiagnosis, causing part replacement with reappearance of the malfunction.
    • If an intermittent malfunction exists refer to General Electrical Diagnosis Cell 4 in Wiring Systems.

Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

  1. This step checks for the pull up voltage from the PCM.

    2.

  2. This step checks for a short to voltage.

    3.

  3. This step checks for a short to ground.

DTC C0239 TCS Spark Retard Monitoring Malfunction

Step

Action

Value(s)

Yes

No

1

Was the Diagnostic System Check performed?

Go to Step 2

Go to Diagnostic System Check

2

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the EBTCM connector C1.
  3. Install the J 39700 Universal Pinout Box using the J 39700-530 cable adapter to the EBTCM harness connector C1 only.
  4. Turn the ignition switch to the RUN position, engine off.
  5. Using J 39200 DMM, measure the voltage at terminal 19 of J 39700 .

Is the voltage within the range specified in the value(s) column?

Battery volts

Go to Step 3

Go to Step 6

3

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the PCM connector C1.
  3. Turn the ignition switch to the RUN position, engine off.
  4. Using J 39200 DMM, measure the voltage at terminal 19 of J 39700 .

Is the voltage within the range specified in the value(s) column?

Above 1V

Go to Step 4

Go to Step 5

4

Repair CKT 1687 for a short to voltage. Refer to Repair Procedures Cell 5 in Electrical Diagnosis.

Is the repair complete?

--

Go to Diagnostic System Check

--

5

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

Is the replacement complete?

--

Go to Diagnostic System Check

--

6

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the PCM connector C1.
  3. Using J 39200 DMM, measure the resistance between terminals 19 and 15 of J 39700 .

Is the resistance within the range specified in the value(s) column?

OL (infinite)

Go to Step 8

Go to Step 7

7

Repair CKT 1687 for a short to ground. Refer to Repair Procedures Cell 5 in Electrical Diagnosis.

Is the repair complete?

--

Go to Diagnostic System Check

--

8

Using J 39200 DMM, measure the resistance between terminal 19 of J 39700 and terminal 30 of the PCM connector C1.

Is the resistance within the range specified in the value(s) column?

0-5ohms

Go to Step 10

Go to Step 9

9

Repair CKT 1687 for an open. Refer to Repair Procedures Cell 5 in Electrical Diagnosis.

Is the repair complete?

--

Go to Diagnostic System Check

--

10

Suspect the PCM. Refer to Engine Controls.

Is the repair complete?

--

Go to Diagnostic System Check

--