P1689

Diagnostic Chart (Part 1 Of 2):

Diagnostic Chart (Part 2 Of 2):

Schematic:

CIRCUIT DESCRIPTION
The Electronic Brake And Traction Control Module (EBTCM) controls the PWM signal on the Desired Torque circuit while monitoring the wheel speed sensors to detect slippage. The PCM monitors the PWM signal and reduces engine torque as needed by retarding ignition timing, decreasing boost duty cycle (Vin 1), increasing air/fuel ratio, or, in severe cases, shutting OFF up to three fuel injectors. The PCM sends a PWM signal to the EBTCM on the delivered torque circuit informing the EBTCM of response made to the desired torque signal. If the PCM detects a problem with the delivered torque circuit, DTC P1689 will set and traction control will be disabled. An ABS/TCS DTC may also be set. For further ABS/TCS DTC information, refer to ABS Description in Antilock Brake Systems.

CONDITIONS FOR RUNNING THE DTC
The ignition is ON.

CONDITIONS FOR SETTING THE DTC
^ An improper voltage level has been detected on output circuit for the traction control delivered torque output circuit.
^ The above conditions are present for at least 30 seconds.

ACTION TAKEN WHEN THE DTC SETS
^ The PCM will not illuminate the Malfunction Indicator Lamp (MIL).
^ The PCM will store conditions which were present when the DTC set as Failure Records data only. This information will not be stored as Freeze Frame data.

CONDITIONS FOR CLEARING THE MIL/DTC
^ A History DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
^ The DTC can be cleared by using a scan tool.

DIAGNOSTIC AIDS
Check for the following conditions:
^ Poor connection at the PCM - Inspect harness connectors for the following conditions:
- Backed out terminals
- Improper mating
- Broken locks
- Improperly formed or damaged terminals
- Poor terminal to wire connection
^ Damaged harness - Inspect the wiring harness for damage.
^ If the harness appears to be OK, disconnect the PCM, turn ON the ignition and observe a Digital Multimeter connected between the Traction Control Delivered Torque control circuit and ground at the PCM harness connector while moving connectors and wiring harnesses related to the EBTCM. A change in voltage will indicate the location of the malfunction.

If the DTC cannot be duplicated and is determined to be intermittent, reviewing the Failure Records can be useful in determining when the DTC was last set. Also refer to Testing for Intermittent and Poor Connections in Diagrams.

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table.
2. Normally, ignition feed voltage should be present on the control circuit with the PCM disconnected and the ignition turned ON.
3. Checks for a shorted component or a short to B+ on the control circuit. Either condition would result in a measured current of over 500 milliamps. Also checks for a component that is going open while being operated, resulting in a measured current of 0 milliamps.
4. Checks for a short to voltage on the control circuit.
15. This vehicle is equipped with a PCM which utilizes an Electrically Erasable Programmable Read Only Memory (EEPROM). When the PCM is being replaced, the new PCM must be programmed.