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SWITCH - SPEED CONTROL DESCRIPTION There are two separate switch pods that operate the speed control system. The steering-wheel-mounted switches The individual switches cannot be repaired. If one switch fails, the entire switch module must be replaced. OPERATION When speed control is selected by depressing the ON, OFF switch, the PCM allows a set speed to be stored in its The speed control can be disengaged manually by: • Stepping on the brake pedal • Depressing the OFF switch • Depressing the CANCEL switch. The speed control can be disengaged also by any of the following conditions: • An indication of Park or Neutral • The VSS signal increases at a rate of 10 mph per second (indicates that the co-efficient of friction between the • Depressing the clutch pedal. • Excessive engine rpm (indicates that the transmission may be in a low gear) • The VSS signal decreases at a rate of 10 mph per second (indicates that the vehicle may have decelerated at • If the actual speed is not within 20 mph of the set speed The previous disengagement conditions are programmed for added safety. Once the speed control has been disengaged, depressing the ACCEL switch restores the vehicle to the target NOTE: Depressing the OFF switch will erase the set speed stored in the PCM’s RAM. If, while the speed control is engaged, the driver wishes to increase vehicle speed, the PCM is programmed for an 9 tap-up 9 feature in which vehicle speed increases at a rate of approximately 2 mph for each momentary switch activation of The PCM also provides a means to decelerate without disengaging speed control. To decelerate from an existing Multiplexing The PCM sends out 5 volts through a fixed resistor and monitors the voltage change between the fixed resistor and Another resistor has been added to the ’at rest circuit’ causing the PCM to never see 5 volts. This was done for 8P - 10 SPEED CONTROL KJ |