Diagnostic Aids

Perform this circuit test when directed by other CIRCUIT TESTS. This test is only intended to diagnose:

• Throttle plate linkage.
• Test conditions.

1. Check For Codes 121, 122 & 123
   
   Disconnect cruise control servo wiring harness connector (if equipped). Perform KOEO SELF-TEST  . If Code 121, 122 or 123 is present, go to appropriate CIRCUIT TEST. See DIAGNOSTIC TROUBLE CODE REFERENCE CHARTS  , and service codes as necessary. If Code 111 (pass code) is displayed, go to next step. If no code is displayed, go to CIRCUIT TEST QA  .
2. Check Throttle Linkage
   
   Check throttle and linkage for sticking and binding. If throttle and linkage are okay, replace Throttle Position (TP) sensor and repeat QUICK TEST  . If throttle or linkage is binding, repair as necessary and repeat QUICK TEST  .