Circuit Description
The PCM supplies 5 volts on the desired torque circuit to the Electronic Brake and Traction Control Module (EBTCM). The EBTCM toggles this 5 volt signal to a ground in order to produce a duty cycle signal. The signal is proportional to the amount of engine output torque reduction requested by the EBTCM. The EBTCM supplies this signal when it detects a wheel slip. In order to reduce engine output torque, the PCM reduces the amount of spark advance and in some cases, the PCM disables a number of fuel injectors. This diagnostic test checks for a Desired Torque signal failure. If the PCM does not receive the Desired torque signal, this DTC sets.
Conditions for Running the DTC
| • | The traction control has not failed. |
| • | The engine speed is greater than 500 RPM for 20 seconds. |
Conditions for Setting the DTC
The desired torque signal is not received by the PCM for 3 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 the scan tool Clear Info function. |
Diagnostic Aids
Important: Remove any debris from the connector surfaces before servicing a component. Inspect the connector gaskets when diagnosing/replacing a component. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion.
Important: Do not perform this diagnostic procedure if the customer's concern is not related to the ABS and/or the Traction Control system(s).
The following may cause an intermittent:
| • | Mis-routed harness |
| • | Rubbed through wire insulation |
| • | Broken wire inside the insulation |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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This step determines if the EBTCM is receiving the 5.0 volts from the PCM. Use the connector test kit adaptor J 35616 when probing the EBTCM connector.
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If no DTCs are set, inspect connections at the EBTCM.
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This DTC will not report a pass. The scan tool status for this DTC will never report a pass. The scan tool will only display when the diagnostic fails. The repair is not complete if the scan tool indicates that the diagnostic ran and failed.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | ||
|
Important: Perform this diagnostic procedure only if the customer's concern is related to the ABS and/or the Traction Control system(s). Refer to Self-Diagnostics in ABS Brakes.
Does the voltage measure at or near the specified value? | 5.0 V | |||
|
Important: Verify communication between the scan tool and the EBTCM before you continue with this table. If you can not establish communications, refer to Self-Diagnostics in ABS Brakes. Are any ABS/TCS DTCs or BCM DTCs set? | -- | Go to ABS Brakes or Body and Accessories for further diagnosis | Go to Diagnostic Aids | |
4 | Probe the Desired Torque circuit using a that is connected to a good ground. Does the voltage measure at or near the specified value? | B+ | ||
5 | Probe the Desired Torque circuit using a J 35616-200 Test Lamp that is connected to B+. Does the test lamp illuminate? | -- | ||
6 | Test for an open in the Desired Torque circuit. Refer to Wiring Repairs . Did you find and correct the condition? | -- | ||
7 | Repair the short to B+ on the Desired Torque circuit. Refer to Wiring Repairs . Did you complete the repair? | -- | -- | |
8 | Repair the short to ground on the Desired Torque circuit. Refer to Wiring Repairs . Did you complete the repair? | -- | -- | |
9 | Inspect for faulty connections at the PCM. Refer to Intermittents and Poor Connections Diagnosis and Connector Repairs . Did you find and correct the condition? | -- | ||
10 |
Important:: The replacement PCM must be programmed. Refer to Powertrain Control Module Replacement/Programming . Replace the PCM. Did you complete the replacement? | -- | -- | |
Does the DTC reset? | -- | |||
12 | Does the scan tool indicate any DTCs set that you have not diagnosed? | -- | Go to applicable DTC | System OK |
