Detailed guide for MID 128 PID 91 FMI 9
Back to top ↑MID 128 PID 91 FMI 9 - Accelerator Pedal Position
**Fault Type:** Abnormal update rate
Fault Condition
- Missing signal from VECU
Possible Symptoms
- N/A - diagnostic information only (no performance symptoms noted in documentation)
Possible Causes
- J1708 pedal information not available
- Communication failure between VECU and EMS
- VECU not broadcasting accelerator pedal position
System Information
The Vehicle Electronic Control Unit (VECU) directly monitors the Throttle Position (TP) Sensor located above the accelerator pedal. The VECU broadcasts this information on the serial data lines to other ECUs.
Diagnostic Tips
1. Check VECU for fault codes related to accelerator pedal
2. Verify accelerator pedal sensor operation with diagnostic tool
3. Inspect J1708 data link wiring and communication
4. Check VECU power and ground connections
5. Monitor accelerator pedal position data in VECU with Premium Tech Tool (PTT)
Mechanic community notes for MID 128 PID 91 FMI 9
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