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DTC B2725: Select Switch Circuit Malfunction: Testing

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  1. If ATC system check was performed, go to next step. If system check was not performed, see ATC SYSTEM CHECK  .
  2. Turn ignition off. Connect scan tool to DLC. Turn ignition to run position (engine off). Using scan tool, record all freeze frame and failure records. Turn ignition off. Disconnect select switch connectors C1 and C2. Turn ignition to run position (engine off). Using a DVOM, measure voltage between ground and Light Green/Black wire circuit terminal "A" at connector C1. See WIRING DIAGRAMS  . If voltage is 7-9 volts, go to next step. If voltage is not 7-9 volts, go to step 9)
  3. Turn ignition off. Disconnect ATC control module connectors C1 and C2. Turn ignition to run position (engine off). Using a DVOM, measure voltage between ground and Light Blue/Black wire circuit terminal "B" at select switch connector C1. If voltage is zero volts, go to next step. If more than zero volts is measured, go to step 11).
  4. Connect self-powered test light between ground and Light Blue/Black wire circuit terminal "B" at select switch connector C1. If test light is on, go to next step. If test light is off, go to step 6).
  5. Locate and repair short to ground in Light Blue/Black wire circuit. When repair is complete, go to step 18).
  6. Using a DVOM, measure resistance of Light Blue/Black wire circuit from terminal "B" of select switch connector C1 to ATC control module connector terminal F16. See WIRING DIAGRAMS  . If resistance is zero ohms, go to next step. If resistance is more than zero ohms, go to step 8).
  7. Replace select switch. See REMOVAL & INSTALLATION  . When replacement is complete, go to step 18).
  8. Locate and repair open in Light Blue/Black wire circuit between ATC control module and select switch connectors. When repair is complete, go to step 18).
  9. If voltage in step 2) was more than 9 volts, go to next step. If voltage in step 2) was less than 9 volts, go to step 14).
  10. Turn ignition off. Disconnect ATC control module connector C1. Turn ignition to run position (engine off). Using a DVOM, measure voltage between ground and Light Green/Black wire terminal "A" at select switch connector C1. If voltage is zero volts, go to step 12). If voltage is more than zero volts, go to step 13).
  11. Locate and repair short to voltage in Light Blue/Black wire circuit. When repair is complete, go to step 18).
  12. Replace ATC control module. See REMOVAL & INSTALLATION  . When repair is complete, go to step 18).
  13. Locate and repair short to voltage in Light Green/Black wire circuit. When repair is complete, go to step 18).
  14. Connect self-powered test light between ground and Light Green/Black wire terminal "A" at select switch connector C1. If test light is on, go to next step. If test light is off, go to step 16).
  15. Locate and repair short to ground in Light Green/Black wire circuit. When repair is complete, go to step 18).
  16. Using a DVOM, measure resistance of Light Green/Black wire circuit from select switch connector terminal "A" to ATC control module connector terminal F14. See WIRING DIAGRAMS  . If resistance is zero ohms, go to step 12). If resistance is more than zero ohms, go to next step.
  17. Locate and repair open in Light Green/Black wire circuit between select switch connector and ATC control module connector. When repair is complete, go to next step.
  18. Turn ignition off. Reconnect all disconnected components. Set parking brake. Start engine and run at idle. Shift transmission to "N" position. Shift transfer case through all modes, allowing time between each shift for transfer case to complete shift request. Using scan tool, select "Specific DTC" and enter DTC B2725. If test runs and passes, system is functioning properly. If test does not run and pass, repeat test from step 1).
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