Ignition Switch Continuity Test
NOTE:
For an "engine not cranking" condition with A/T, determine if condition exists in both Park and Neutral positions. If condition occurs in one position and not the other, a more probable cause is the neutral start switch. See appropriate TRANSMISSION SERVICING - A/T article in AUTOMATIC TRANS SERVICE section
- Test ignition switch operation by rotating cylinder/key through all switch positions. Movement should feel smooth with no sticking or binding. Cylinder/key should return from START position to RUN position without assistance. Inspect and repair if necessary.
- Remove instrument panel lower cover. Disconnect multiple connector from ignition switch. Connect a self-powered test lamp or ohmmeter between blade terminals indicated in following steps. See Fig 1 .
- Continuity between any blade and chassis ground should not exist in any switch position except proof circuits in START position. With ignition switch in ACC position, continuity should exist between terminals A-1 through B-5 only.
- With ignition switch in LOCK and OFF positions, there should not be continuity.
- With ignition switch in RUN position, continuity should exist between terminals A-1 and B-1, A-2 and B-2, A-3 and B-3, A-4 and B-4, and I-1 and B-5.
- With ignition switch in START position, continuity should exist between terminals I-1 and B-5, I-2 and B-1, STA and B-4, P-1 and GND, and P-2 and GND.
NOTE:
Before performing the following tests, place A/T in Neutral or Park and M/T in Neutral. Disconnect vacuum line to thermactor by-pass valve. After tests, run engine 3 minutes before connecting vacuum line.