Turn Signals: Description and Operation

TURN SIGNAL LAMPS
The turn signal lamps may only be activated with the ignition switch in RUN or BULB TEST position. The T/SIG fuse supplies ignition voltage to the turn signal switch. When the turn signal switch is placed in either the left or right position, the turn signal switch sends an ignition voltage to the hazard lamp/turn signal flasher, which sends an on-off signal to the turn signal switch. When the turn signal switch receives the on-off signal it will send that signal to the following lamps on the LH or RH side:
- The Rear Turn Lamp
- The Turn Signal Indicator
- The Sidemarker Lamp
- The Sideview Mirror (Pontiac Thunder only)

The turn signal switch also sends a separate on-off signal to the Daytime Running Lamps (DRL) control module, which relays the signal to the appropriate front turn signal. The front turn signals are grounded at G101 and G102. The rear turn signals are grounded at G401. The sidemarker lamps are grounded through the corresponding front parklamp.

The sideview mirror turn signals are a bank of LEDs placed behind the mirror glass.

The hazard lamps operate on battery voltage. The HAZARD fuse supplies battery voltage to the turn signal switch. When the hazard switch is pressed, the turn signal switch sends battery voltage to the hazard lamp/turn signal flasher, which sends an on-off signal to the turn signal switch. The turn signal switch send the on-off signal to all the turn signal lamps, causing all the lamps to flash including both IPC turn signal indicators. The hazard lamp/turn signal flasher is grounded at G200.

When the parklamps are ON, the sidemarker lamps receive voltage from the park lamp supply voltage circuit and illuminate. The sidemarker lamp is grounded through the corresponding rear turn signal. When the turn signal switch is place in the left or right hand position, the rear turn signal illuminates and the sidemarker lamp will loose its ground, causing the sidemarker lamp to turn off when the turn signals are on and to illuminate again when the turn signal is off.

TURN SIGNAL LAMPS (EXPORT)
The HAZARD fuse and T/SIG fuse, supplies battery and ignition positive voltage to the turn signal switch. The turn signal lamps may only be activated with the ignition switch in RUN or BULB TEST position. When the turn signal switch is placed in either the left or right position, current flow is from the turn signal switch to the hazard lamp/turn signal flasher and back to the turn signal switch assembly. The hazard lamp/turn signal flasher sends an on-off voltage signal to the turn signal switch, which sends the on-off signal to either the left or right rear turn signal, front turn signal, repeater lamp, and their Instrument Cluster Panel (IPC) indicator. The hazards lamps operate on battery voltage. When the hazard switch is pressed, all the turn signal lamps will flash including both IPC turn signal indicators. The hazard lamp/turn signal flasher is grounded at G200. The LF turn signal and LF repeater lamp are grounded at G101. The RF turn signal and RF repeater lamp are grounded at G102. The rear turn signals are grounded at G401.

TURN SIGNALS
The IPC illuminates the right or left turn signal indicator when the IPC detects a turn signal request or a hazard request.