Cruise Control System Circuit Description. Opel Sintra 1999

For 1990-2009 cars

The stepper motor cruise control (SMCC) is a speed control system that maintains a desired vehicle speed under normal driving conditions. Steep grades, up or down, may cause variations in the selected speeds. The cruise control system has the capability to perform the following functions:

• | Cruise

• | Coast

• | Resume speed

• | Accelerate

• | Tap-up

• | Tap-down

The cruise control module contains the following components:

• | An electronic controller

• | An electric motor

The controller performs the following functions:

• | Monitors the vehicle speed

• | Operates the electric motor

In response to the controller, the motor moves a connecting strap. The connecting strap is attached to the cruise control cable. The cable moves the throttle linkage in order to vary throttle position in order to maintain the desired cruise speed. The cruise control module contains a low speed limit. This prevents the system engagement below a minimum speed of approximately 40 km/h (25 mph). The module is controlled by mode control switches. The mode control switches are located on the turn signal lever. The cruise control is in the standby disabled mode until all conditions inconsistent with the cruise control operation are cleared.

Ignition voltage is supplied from the CRUISE fuse, through CKT 739 to terminal F of the cruise control module. The cruise control module receives ground at terminal E through CKT 1150 and from G201. When the slider switch is moved to the ON position, battery voltage is applied through CKT 397 to terminal A of the cruise control module connector.

If the brake pedal is not depressed, battery voltage is present from CKT 739 through the cruise control release switch and CKT 86 to the module terminal D. If the brake pedal is depressed, battery voltage is supplied from the STOPLAMP fuse, through CKT 140, the stoplamp switch and CKT 17 to the module terminal G. Terminal G must see current flow through the center high-mounted stop lamp (CHMSL) bulbs in order for the cruise to operate and disable properly.

When the slider switch is moved to the R/A position, battery voltage is applied through CKT 87 to terminal C of the module. With the set switch depressed, battery voltage is present through CKT 84 to module terminal B. Cruise control module connector terminal K is the speed signal terminal through CKT 389. In operation, voltage will oscillate between a high of 4 to 5 volts and a low of near ground. Terminal J is used in order to signal the powertrain control module (PCM) when the cruise control is engaged through CKT 85. The PCM will then determine the correct shift pattern for the transmission. Terminal H is used by the PCM through CKT 83, in order to inhibit cruise control when conditions not consistent with cruise control operation are present. The PCM will inhibit the cruise control when any of the following conditions exists:

• | The vehicle speed is less than 40 km/h (25 mph).

• | The transaxle range switch is in one of the following positions:

• | PARK

• | NEUTRAL

• | 1st GEAR

• | An over/under battery condition exists.

• | The engine is running at low RPMs.

• | The engine is running at high RPMs (Fuel cut-off).