1-4 Shift Light (Man. Trans. Corvette)
- This testing procedures assumes that a problem exists with the 1-4 shift light. Use this procedure only if the light will illuminate, or illuminates all of the time.
- Turn ignition on, with engine off. Note shift light. Shift light should not be on. If light is on, check for a short to ground between the bulb and the ECM, or a bad ECM.
- With ignition on and engine off, ground "test" terminal "B" of ALDL connector. The "SERVICE ENGINE SOON" light should start to flash and 1-4 shift light should come on. If light comes on, go to next step. If "SERVICE ENGINE SOON" light does not flash, perform DIAGNOSTIC CIRCUIT CHECK as described in the BASIC TESTING
article.
- If 1-4 shift light does not come on, ground ECM terminal C13 using a jumper wire. If light still does not come on, check for blown GAUGES fuse, blown bulb or open circuit between fuse and ECM. If light comes on when grounding terminal C3 with a jumper wire, problem is a bad ECM connection or bad ECM.
Courtesy of GENERAL MOTORS CORP.