Diagnostic Aids

Intermittent problem may be caused by poor electrical connections. Check for poor connections at transfer case switch and PCM/TCM. If connections are okay, see appropriate TRANSFER CASE article.

Fig 1: 4WD Switch Signal Check Schematic - 1994

Courtesy of GENERAL MOTORS CORP.

Fig 2: 4WD Switch Signal Check Flow Chart - 1994

Courtesy of GENERAL MOTORS CORP.