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DTC P0550: Power Steering Switch Malfunction: Testing

NOTE: Ensure freeze frame data has been recorded. Check for service bulletins and on-line information.
  1. Turn ignition on. Ensure steering wheel is straight. Using scan tool, access PID/DATA MONITOR. Record PID data for PSP SW. If PID is on, go to next step. If PID is off, problem is not present. Check for intermittent problem. See TROUBLE SHOOTING - NO CODES article.
  2. Turn ignition off. Disconnect PSP switch connector. Turn ignition on. If PID is on, go to next step. If PID is off, replace switch. After repair, go to step  4 .
  3. Disconnect PCM connector. PCM is mounted to passenger floor, behind glove box. Check continuity between PSP switch harness connector and ground. If continuity is not present, go to next step. If continuity is present, repair short to ground on Black/Blue wire between PSP switch and PCM. After repair, go to next step.
  4. Reconnect all components. Start engine. Using scan tool, clear DTC. Drive vehicle at more than 37 MPH for one minute. Ensure ECT PID is more than 140 °F. Recheck pending DTCs. If DTC P0550 is pending, replace PCM and go to next step. If DTC P0550 is not pending, go to next step.
  5. Perform after repair procedure. See AFTER REPAIR PROCEDURE  . If no DTC is present, testing is complete. If any DTC is present, go to appropriate test for diagnosis and repair.
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