RAM 2500 Truck 2WD L6-359 5.9L DSL Turbo VIN D FI (1997)
Ignition Switch: Description and Operation
IGNITION SWITCH AND KEY LOCK CYLINDER
The ignition switch is located on the steering column. The Key-In-Switch is located in the ignition switch module. For electrical diagnosis of the
Key-In-Switch, refer to Chime/Buzzer Warning Systems. For removal/installation of either the key lock cylinder or ignition switch, refer to
Ignition Switch and Key Cylinder Removal/Installation.
Column Shift Interlock
The column shift interlock is used to lock the transmission shifter in the Park position when the key is in the Off position. The interlock device is
located within the steering column assembly and is not serviceable. If repair is necessary, the steering column assembly must be replaced.
CIRCUIT OPERATION
When the ignition switch is in the RUN position, it connects circuit A2 from fuse 2 in the Power Distribution Center (PDC) to circuit A22. Circuit
A22 connects to the fuse block. Through the fuse block, circuit A22 feeds circuits A20, L10, F23, C1 and F21. Circuits A20, L10, F23, and C1 are
protected by separate fuses. A circuit breaker protects circuit F21.
When the ignition switch is in the START or RUN position, it connects circuit A1 from fuse 3 in the PDC to circuit A21. Circuit A21 powers
circuits F18, F12, and F14 through the fuse block. Separate fuses protect each circuit.
In the START position, the ignition switch connects circuit A1 from fuse 3 in the PDC to circuit A41. Circuit A41 connects to either the clutch
pedal position sensor or the clutch pedal position switch bypass jumper. Also in the START position, the ignition switch connects circuit G9 to
ground.
In the ACCESSORY or RUN position, the ignition switch connects circuit A1 to circuit A31. Circuit A31 connects to the fuse block and feeds
circuits F30, L5, X12, and V6. Separate fuses protect each circuit.
Battery Feed
Circuit A14 from fuse 8 in the Power Distribution Center (PDC) supplies battery voltage to cavity A22 of the Powertrain Control Module (PCM).
Ground
Circuit Z12 connects to cavities A31 and A32 of the Powertrain Control Module (PCM). The Z12 circuit provides ground for PCM internal
drivers that operate high current devices like the injectors and ignition coil.
