• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
5-Volt Reference | P1392 | P0317, P1392 | P1393 | P1391 |
Rough Road Sensor Signal | P1392 | P0317, P1392 | P1393 | P1391 |
Low Reference | -- | P1391 | -- | P1391 |
Circuit | Short to Ground | Open | Short to Voltage |
---|---|---|---|
Operating Conditions: Engine operating in Closed Loop Parameter Normal Range: 1.1-3.7 Volts | |||
5-Volt Reference | 0.0 Volts | 0.0 Volts | 5.0 Volts* |
Rough Road Sensor Signal | 0.0 Volts | 0.0 Volts | 5.0 Volts* |
Low Reference | -- | 0.0 Volts | 5.0 Volts* |
* Internal ECM or sensor damage may occur if the circuit is shorted to B+. |
The engine control module (ECM) identifies engine misfire by detecting variations in crankshaft speed. Crankshaft speed variations can also occur when a vehicle is operating over a rough road. The ECM receives a rough road signal by a gravity sensing rough road sensor or an electronic brake control module (EBCM), if equipped with the antilock brake system (ABS). The ABS can detect if the vehicle is on the rough surface based on wheel acceleration/deceleration data supplied by each wheel speed sensor. This information is sent to the ECM by the EBCM through a serial data line. The rough road sensor is a vertical low G-acceleration sensor. By sensing vertical acceleration caused by rough road conditions, the ECM determines if the changes in crankshaft speed are due to engine misfire or are driveline induced. The rough road sensor consist of the following circuits:
• | A 5-volt reference |
• | A rough road sensor signal |
• | A low reference |
• | The engine has been running for greater than 10 seconds. |
• | DTC P0317 runs continuously once the above condition is met for greater than 10 seconds. |
The ECM does not detect a rough road signal for greater than 9 seconds.
DTC P0317 is a Type C DTC.
DTC P0317 is a Type C DTC.
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Control Module References for scan tool information
⇒ | If the circuit tests normal, refer to Symptoms - Antilock Brake System . |
⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM. |
Important: The 5-volt reference circuits are internally and externally connected at the ECM. Other component DTCs may be set. If other DTCs are set, review the electrical schematic and diagnose the applicable circuits and components.
⇒ | If less than the specified range, test the 5-volt reference circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the ECM. |
⇒ | If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the ECM. |
⇒ | If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the ECM. |
⇒ | If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for engine control module replacement, setup, and programming |