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System Check

WARNING: This page is about a different car, the 1993 Cadillac Fleetwood. However, it is still accessible from the selected car via links, so may be relevant.
  1. Turn ignition switch to RUN position. Enter ECC diagnostic mode. See ENTERING DIAGNOSTIC MODE  . If ECC Code 50 is set, perform ECC CODE 50 (LOSS OF VES STEERING) test. If no codes are set, or if ECC Code 150 is set, check for ECM Code 24.
  2. If ECM Code 24 is set, check Vehicle Speed Sensor (VSS) and its circuit. See TESTS W/CODES - 5.7L article in the ENGINE PERFORMANCE. If ECM Code 24 is NOT set, turn ignition off. Remove 3-amp C/C fuse from engine compartment fuse block. Turn ignition switch to RUN position. Enter ECC diagnostic mode. While observing AUTO fan status light, install C/C fuse.
  3. If AUTO fan status light did not come on momentarily, perform VES INPUT TEST. If AUTO fan status light came on momentarily, raise and support rear of vehicle with wheels off ground. Block front wheels. Connect scan tester. Select VES DUTY CYCLE. Start engine. Place transmission in gear. Accelerate to 50 MPH.
  4. If duty cycle does not increase as vehicle speed increases, perform VES INPUT TEST  . If duty cycle increases as vehicle speed increases, compare steering effort while test driving vehicle at high speed with C/C fuse first removed, and then installed.
  5. With fuse installed, if steering effort did not increase as vehicle speed increased, problem is mechanical. Proceed to STEERING SYSTEM - POWER article in the STEERING. With fuse installed, if steering effort increased as vehicle speed increased, system is okay. If Code 150 was set as indicated in step 1), an intermittent problem may exist.
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