Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSGMC1999FORWARD CONTROL 5.7 R, AUTOMATICREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 84 (DIAGNOSIS - VT25-E)SELF-DIAGNOSTIC SYSTEMDIAGNOSTIC TROUBLE CODE DEFINITIONS
1999 GMC Forward Control 5.7 R, Automatic
Diagnostic Trouble Code Definitions
1999 GMC Forward Control 5.7 R, AutomaticSECTION Diagnostic Trouble Code Definitions
WARNING: This page is about a different car, the 2003 Saturn Vue and 2002 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
Only transaxle related DTCs are listed. See DIAGNOSTIC TROUBLE CODE DEFINITIONS
table. For engine-related DTC definitions and diagnosis, see appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE. These DTCs pertain to engine performance and must be repaired first, as engine performance and related component signals will affect transaxle operation and diagnosis.
There are 4 types of DTC categories:
- Type "A" - Emissions related. Illuminates MIL the first time DTC sets.
- Type "B" - Emissions related. Illuminates MIL if fault is active for 2 consecutive driving cycles.
- Type "C" - Non-emissions related. Does not illuminate MIL, but may illuminate SERVICE light.
- Type "D" - Non-emissions related. Does not illuminate MIL or SERVICE light.
DIAGNOSTIC TROUBLE CODE DEFINITIONS
| DTC | Circuit & Fault Definitions |
|---|---|
| P0218 | Transmission Fluid Overtemperature |
| P0562 | System Voltage Low |
| P0563 | System Voltage High |
| P0601 | TCM Read Only Memory |
| P0602 | TCM Not Programmed |
| P0603 | TCM Long Term Memory |
| P0604 | TCM Random Access Memory |
| P0606 | TCM Internal Performance |
| P0705 | PNP Switch Circuit |
| P0711 | TFT Sensor Performance |
| P0712 | TFT Sensor Low Voltage |
| P0713 | TFT Sensor High Voltage |
| P0716 | ISS Performance |
| P0717 | ISS Low Voltage |
| P0719 | Stoplamp Switch Circuit Low Voltage |
| P0722 | OSS Low Voltage |
| P0723 | OSS Intermittent |
| P0724 | Stoplamp Switch Circuit High Voltage |
| P0727 | Engine Speed No Signal |
| P0741 | TCC System - Stuck Off |
| P0742 | TCC System - Stuck On |
| P0841 | TFP Sensor Performance |
| P0842 | TFP Sensor Circuit Low Voltage |
| P0843 | TFP Sensor Circuit High Voltage |
| P0960 | Line PC Solenoid Circuit Open |
| P0961 | Line PC Solenoid Performance |
| P0962 | Line PC Solenoid Low Voltage |
| P0964 | TCC PC Solenoid Circuit Open |
| P0965 | TCC PC Solenoid Performance |
| P0966 | TCC PC Solenoid Low Voltage |
| P1756 | PNP Switch Indicates Park Or Neutral With Drive Ratio |
| P1758 | PNP Switch Indicates Drive Without Drive Ratio |
| P1779 | Torque Delivered Signal |
| P1780 | Torque Reduction Signal |
| P1882 | Ratio Control Performance |
| P1883 | Ratio Control Motor Coil "A1" Circuit |
| P1884 | Ratio Control Motor Coil "A2" Circuit |
| P1885 | Ratio Control Motor Coil "B1" Circuit |
| P1886 | Ratio Control Motor Coil "B2" Circuit |
| P1888 | TCC Enable Solenoid Circuit Low Voltage |
| P1889 | TCC Enable Solenoid Circuit High Voltage |
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.