SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSGMC1999FORWARD CONTROL 5.7 R, AUTOMATICREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 83 (ENGINE CONTROLS - SELF-DIAGNOSTICS)DIAGNOSTIC TESTSDTC P0705: TRANSMISSION RANGE SWITCH CIRCUITDIAGNOSTIC PROCEDURES
1999 GMC Forward Control 5.7 R, Automatic

Diagnostic Procedures

1999 GMC Forward Control 5.7 R, AutomaticSECTION Diagnostic Procedures
WARNING: This page is about a different car, the 2002 Saturn LW200, 2002 Saturn L200, and 2002 Saturn L100. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Transaxle range switch is located on side of transaxle behind shift lever. Electronic PRNDL module is located next to shift lever in center console.
  1. Turn ignition on. Using scan tool, monitor TRANSMISSION RANGE while moving selector lever through each position. If scan tool display matches actual selector lever position, DTC may be caused by intermittent condition. See DIAGNOSTIC AIDS  . If scan tool display does not match actual selector lever position, go to next step.
  2. If scan tool display is not blank, go to next step. If scan tool display is blank, check Black/White wire between transaxle range switch and ground for open. If wire is okay, replace transaxle range switch.
  3. Place selector lever in "P" position. If scan tool reads PARK, go to next step. If scan tool does not read PARK, go to step  10 .
  4. Place selector lever in "R" position. If scan tool reads REVERSE, go to next step. If scan tool does not read REVERSE, go to step  16 .
  5. Place selector lever in "N" position. If scan tool reads NEUTRAL, go to next step. If scan tool does not read NEUTRAL, go to step  8 .
  6. If all lights on PRNDL console display are not on, go to next step. If all lights on PRNDL console display are on, check Gray wire between PCM and transaxle range switch for open. If wire is okay, replace PCM.
  7. Disconnect transaxle range switch 4-pin connector. Connect jumper wire between transaxle range switch connector terminal "C" (Gray wire) and ground. Using scan tool, monitor position of "C" of TR SWITCH - P/A/B/C. If scan tool reads OFF, check connector terminals. If connector is okay, replace transaxle range switch. If scan tool does not read OFF, repair open in Gray wire between PCM and transaxle range switch.
  8. Disconnect transaxle range switch 4-pin connector. Using scan tool, monitor position "A" of TR SWITCH - P/A/B/C. If scan tool reads ON, replace transaxle range switch. If scan tool does not read ON, go to next step.
  9. Disconnect electronic PRNDL module at selector lever. If scan tool reads ON, replace electronic PRNDL module. If scan tool does not read ON, check Black/White wire between PCM and transaxle range switch for short to ground. If wire is okay, replace PCM.
  10. Place selector lever in "R" position. If scan tool reads REVERSE, go to next step. If scan tool does not read REVERSE, go to step  21 .
  11. Place selector lever in "N" position. If scan tool reads NEUTRAL, go to next step. If scan tool does not read NEUTRAL, go to step  14 .
  12. Disconnect transaxle range switch 4-pin connector. Using scan tool, monitor position "P" of TR SWITCH - P/A/B/C. If scan tool reads ON, replace transaxle range switch. If scan tool does not read ON, go to next step.
  13. Disconnect electronic PRNDL module at selector lever. If scan tool reads ON, replace electronic PRNDL module. If scan tool does not read ON, check Yellow wire between PCM and transaxle range switch for short to ground. If wire is okay, replace PCM.
  14. If all lights on PRNDL console display are on, go to next step. If all lights on PRNDL console display are not on, check White wire between PCM and transaxle range switch for open. If wire is okay, replace PCM.
  15. Disconnect transaxle range switch 4-pin connector. Connect jumper wire between transaxle range switch connector terminal "A" (White wire) and ground. Using scan tool, monitor position of "P" of TR SWITCH - P/A/B/C. If scan tool reads OFF, check connector terminals. If connector is okay, replace transaxle range switch. If scan tool does not read OFF, repair open in White wire between PCM and transaxle range switch.
  16. Place selector lever in "N" position. If scan tool reads NEUTRAL, go to next step. If scan tool does not read NEUTRAL, go to step  19 .
  17. Disconnect transaxle range switch 4-pin connector. Using scan tool, monitor position "P" of TR SWITCH - P/A/B/C. If scan tool reads ON, replace transaxle range switch. If scan tool does not read ON, go to next step.
  18. Disconnect electronic PRNDL module at selector lever. If scan tool reads ON, replace electronic PRNDL module. If scan tool does not read ON, check White wire between PCM and transaxle range switch for short to ground. If wire is okay, replace PCM.
  19. If all lights on PRNDL console display are on, go to next step. If all lights on PRNDL console display are not on, check Yellow wire between PCM and transaxle range switch for open. If wire is okay, replace PCM.
  20. Disconnect transaxle range switch 4-pin connector. Connect jumper wire between transaxle range switch connector terminal "B" (Yellow wire) and ground. Using scan tool, monitor position of "B" of TR SWITCH - P/A/B/C. If scan tool reads OFF, check connector terminals. If connector is okay, replace transaxle range switch. If scan tool does not read OFF, repair open in Yellow wire between PCM and transaxle range switch.
  21. Place selector lever in "N" position. If scan tool reads NEUTRAL, go to next step. If scan tool does not read NEUTRAL, go to step  24 .
  22. If all lights on PRNDL console display are not on, go to next step. If all lights on PRNDL console display are on, check Black/White wire between PCM and transaxle range switch for open. If wire is okay, replace PCM.
  23. Disconnect transaxle range switch 4-pin connector. Connect jumper wire between transaxle range switch connector terminal "D" (Black/White wire) and ground. Using scan tool, monitor position of "A" of TR SWITCH - P/A/B/C. If scan tool reads OFF, check connector terminals. If connector is okay, replace transaxle range switch. If scan tool does not read OFF, repair open in Black/White wire between PCM and transaxle range switch.
  24. Disconnect transaxle range switch 4-pin connector. Using scan tool, monitor position "C" of TR SWITCH - P/A/B/C. If scan tool reads ON, replace transaxle range switch. If scan tool does not read ON, go to next step.
  25. Disconnect electronic PRNDL module at selector lever. If scan tool reads ON, replace electronic PRNDL module. If scan tool does not read ON, check Gray wire between PCM and transaxle range switch for short to ground. If wire is okay, replace PCM.
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.

Shop Manual-Ready ToolsFree Quote CheckQuote Shield Pro

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.