Test A: Scan Tool Does Not Power Up
- Measure voltage between ground and DLC terminal No. 16 (Red wire). See Fig 1
. If battery voltage exists, go to next step. If battery voltage does not exist, repair open or short to ground in Red wire between instrument panel junction box and DLC.
- Measure resistance between ground and DLC terminal No. 4 (White/Black wire). If resistance is less than 2 ohms, go to next step. If resistance is 2 ohms or more, repair open in White/Black wire between DLC and ground. Ground point is located under left side of instrument panel, mounted to support bracket.
- Inspect DLC for loose or damage terminals. If problem exists, repair as necessary. If problem does not exist, go to next step.
- Scan tool or cable may be defective. Use scan tool user guide to check operation. After repair, go to applicable diagnostic system check. See BODY CONTROL SYSTEM DIAGNOSTIC SYSTEM CHECK
under SELF-DIAGNOSTIC SYSTEM.
Courtesy of GENERAL MOTORS CORP.