Ignition Switch: Description and Operation
RUN POSITIONWhen the ignition switch is in the RUN position, it connects circuit A2 from the Power Distribution Center (PDC) to circuit A22. A 50 amp fuse in cavity E of the PDC protects the A2 and A22 circuits.
Circuit A22 connects to a bus bar in the fuse block. The bus bar feeds circuits C1, F21, F20, and A20. Circuits C1, F20, and A20 are protected by separate fuses. A circuit breaker protects circuit F21.
- Fuse 1, 30 amp, protects circuit C1. Circuit C1 feeds the blower motor switch.
- The 30 amp circuit breaker in cavity 2 of the fuse block protects circuit F21. The F21 circuit feeds the power window switches.
- Fuse 3, 15 amp, protects circuit F20. The F20 circuit is double crimped at the fuse. One branch of circuit F20 feeds just the Airbag Control Module (ACM). The other branch feeds the overhead console, Power- train Control Module (PCM), and the back-up lamp switch.
- Fuse 4, 5 amp, is only used on vehicles with ABS. The fuse protects circuit A20. Circuit A20 provides an input to the ABS control module. Circuit A20 also splices to the ABS power relay and the ABS warning lamp relay.
START POSITION
In the START position, the ignition switch connects circuit A1 from the PDC to circuit A41. Circuit A41 connects to the coil side of the engine starter motor relay. If the vehicle is equipped with a manual transmission, circuit A41 connects to the clutch pedal position switch before reaching the starter motor relay.
Also in the START position, the ignition switch provides ground for the brake lamp switch, parking brake lamp switch, and connects to the ABS module or Rear Wheel Anti-Lock (RWAL) module.
START OR RUN POSITION
In the START or RUN positions, the ignition switch connects circuit Al from the PDC with circuit A21. Circuit A1 connects to fuse C in the PDC. The A21 circuit is double crimped at the fuse block. The branch from the fuse block is spliced to the Automatic Shut Down (ASD) relay, radiator fan relay and the daytime running lamps (DRL) module.
At the fuse block, circuit A21 connects to a bus bar that feeds circuits F14, V34, and G5. Each circuit is protected by a separate fuse.
- Fuse 16, 5 amp, feeds circuit G5. The G5 circuit powers the combination buzzer and the overdrive lamp.
- Fuse 15, 2 amp, feeds circuit V34. Circuit V34 powers the vehicle speed control switch.
- Fuse 14, 15 amp, feeds circuit F14. Circuit F14 is double crimped at fuse 14. One branch of circuit F14 connects to the instrument cluster. The other branch of circuit F14 connects to the ACM.
ACCESSORY POSITION
In the ACCESSORY position, the ignition switch connects circuit A1 from the PDC with circuit A31. Circuit A31 connects to a bus bar in the fuse block that feeds circuits X22, V6, L5, and X12. Each circuit is protected by a separate fuse.
- Fuse 9, 15 amp, feeds circuit X22. Circuit X22 powers the cigar lighter.
- Fuse 10, 20 amp, feeds circuit V6. Circuit V6 powers the wiper system.
- Fuse 11, 20 amp, feeds circuit L5. Circuit L5 is double crimped at fuse 11. One branch of circuit L5 connects to the RWAL module (if equipped). The other L5 branch connects to the turn signal flasher in the fuse block.
- Fuse 12, 10 amp, feeds circuit X12 which powers the radio.