General
The cruise control system is enabled by pressing the non-latching master switch located on the LH steering wheel switch pack. The system is controlled by the Engine Control Module (ECM), which receives commands from the 'SET+' and 'RES' switches, which are also located on the LH steering wheel switch pack. The ECM interprets the messages sent from the steering wheel switches and then controls the speed of the vehicle using electric throttle intervention.
For a detailed description of cruise control operation, refer to ENGINE CONTROL - DESCRIPTION & OPERATION .
Power Distribution
Feed from the positive battery terminal (C0192) is supplied to fuse 53 of the passenger compartment fuse box (C0632) on an R wire. Fuse 53 (C0583) is connected to the ignition switch (C0099 on Td6 vehicles, C0028 on V8 vehicles) by an R wire. When the ignition switch is turned to the 'auxiliary' position, current flows across the switch (C0099 on Td6 vehicles, C0028 on V8 vehicles) to fuse 9 of the passenger compartment fuse box (C0585) on a PB wire. Fuse 9 (C0587) provides an auxiliary ignition feed to the rotary coupler (C0082) on a PY wire.
When the ignition switch is turned to the 'ignition' position, current flows across the switch (C0099 on Td6 vehicles, C0028 on V8 vehicles) to fuse 31 of the passenger compartment fuse box (C0585) on a G wire. Fuse 31 (C0587) provides an ignition feed to the Engine Control Module (ECM) (C0331) on a GB wire.
Throttle Position (TP) Sensor
The TP sensor (C0787) comprises two potentiometer tracks. Track 1 is provided a 5V reference feed by the ECM (C0331) on a Y wire. Track 2 is provided a 5V reference feed by the ECM (C0331) on a YG wire. Track 1 provides a throttle position signal back to the ECM on a W wire. This signal will be approximately 0.5V with the pedal at rest, and 2V at full throttle. Track 2 provides a throttle position signal back to the ECM on a WG wire. This signal will be approximately 0.5V with the throttle at rest, and 4.5V at full throttle. The ECM also provides an earth path for track 1 and track 2 on NG and UG wires respectively.
For more information of TP sensor operation, refer to ENGINE CONTROL - DESCRIPTION & OPERATION .