Circuit Description
The electronic brake control module (EBCM) constantly sends a pulse width modulated signal to the accelerator control and servo module (ASM).
Conditions for Running the DTC
DTC 58 can be set anytime the ignition switch is in the ON position.
Conditions for Setting the DTC
The ASM detects one of the following conditions:
| • | Signal frequency deviates outside of specification |
| • | Signal stops for more than 50 milliseconds |
Action Taken When the DTC Sets
| • | The EBCM disables the traction control system for the duration of the ignition cycle. |
| • | The TRAC OFF warning indicator turns ON. |
Conditions for Clearing the DTC
The condition responsible for setting the DTC no longer exists and the Scan Tool Clear DTCs function is used.
Diagnostic Aids
Thoroughly inspect the wiring and the connectors. An incomplete inspection of the wiring and the connectors may result in a misdiagnosis, causing a part replacement with the reappearance of the malfunction.
The following are possible causes of the malfunction:
| • | An open, high resistance, or a short to ground in the ASM ignition positive voltage circuit |
| • | An open or high resistance in the ASM ground circuits |
| • | An open, high resistance or short in the ASM throttle position circuits |
| • | An internal ASM malfunction |
If an intermittent malfunction exists, refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
Test Description
The numbers below refer to step numbers on the diagnostic table.
-
This step determines if the DTC is current.
-
This step tests the ASM ground circuits.
-
This step tests the ASM ignition positive voltage circuit.
-
This step tests the throttle position circuits of the ASM for an open, high resistance or short.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Schematic Reference: Antilock Brake System Schematics Connector End View Reference: Antilock Brake System Connector End Views | ||||
1 | Did you perform A Diagnostic System Check - ABS? | -- | Go to Step 2 | |
Is DTC 58 set as a current DTC? | -- | Go to Step 3 | Go to Diagnostic Aids | |
Does the resistance for both circuits measure as specified? | 0-5 ohms | Go to Step 4 | Go to Step 5 | |
Does the voltage measure as specified? | Battery Voltage | Go to Step 6 | Go to Step 7 | |
5 | Locate and repair the open or high resistance in the ASM ground circuits. Refer to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 10 | -- |
Test the throttle position circuits of the ASM for an open, high resistance or short. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 10 | Go to Step 8 | |
7 | Locate and repair the open, high resistance or short to ground in the ASM ignition positive voltage circuits. Refer to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 10 | -- |
8 | Inspect for poor connections at the harness connectors of the ASM and electronic brake control module (EBCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 10 | Go to Step 9 |
9 | Replace the ASM. Refer to Accelerator and Servo Control Module Replacement . Did you complete the replacement? | -- | Go to Step 10 | -- |
10 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
