P1717 Torque Reduction Request Circuit Malfunction
The P1717 code indicates that the Powertrain Control Module (PCM) has detected a fault in the torque reduction request signal circuit between the PCM and the Transmission Control Module (TCM), or an internal PCM issue. This signal is essential for momentarily reducing engine torque during gear shifts, ensuring smooth transitions and protecting automatic transmission components.
01. Most Common Causes
- Short, open, or corroded wiring or connectors between PCM and TCM
- Internal data bus communication failure (CAN Bus)
- Outdated PCM/TCM software calibration requiring an update
02. Symptoms You Will Notice
- Harsh or delayed gear shifts
- Check Engine Light illuminated
- Reduced fuel economy
- Transmission may enter limp mode
03. Step-by-Step Diagnosis
Scan for additional codes and freeze frame data
Inspect wiring and connectors between PCM and TCM for damage or corrosion
Test CAN Bus communication integrity
Check for technical service bulletins (TSBs) regarding software updates
Perform component tests on PCM and TCM if no wiring issues found
1. Frequently Asked Questions
Is it safe to drive?▼
You can drive short distances, but the transmission may shift harshly or enter limp mode, which can cause further damage. It's best to diagnose and repair promptly.
How much does it cost to fix?▼
Repair costs typically range from $150 to $1,200, depending on whether the issue is a simple wiring repair or requires replacing the PCM or TCM.