Description - Chrysler Vehicle User Manual

TJ
SERVO (Continued)
Fig. 3 SPEED CONTROL SERVO LOCATION
1 - BRAKE POWER BOOSTER
2 - VACUUM LINE
3 - SERVO
4 - BRACKET BOLTS (3)
5 - SERVO MOUNTING BRACKET
Fig. 4 SERVO CABLE CLIP REMOVE/INSTALL -
1 - SERVO MOUNTING NUTS (2)
2 - SERVO
3 - CABLE RETAINING CLIP
4 - SERVO CABLE AND SLEEVE
TYPICAL
SWITCH

DESCRIPTION

There are two separate switch pods that operate
the speed control
mounted switches use multiplexed circuits to provide
inputs to the PCM for ON, OFF, RESUME, ACCEL-
ERATE, SET, DECEL and CANCEL modes. Refer to
the owner's manual for more information on speed
control switch functions and setting procedures.
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 RAM for speed control. To store a set
speed, depress the SET switch while the vehicle is
moving at a speed between approximately 35 and 85
mph. In order for the speed control to engage, the
brakes cannot be applied, nor can the gear selector
be indicating the transmission is in Park or Neutral.
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 road surface and tires is extremely low)
• Depressing the clutch pedal.
• Excessive engine rpm (indicates that the trans-
mission 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 an extremely high rate)
• If the actual speed is not within 20 mph of the
set speed
The previous disengagement conditions are pro-
grammed for added safety.
Once the speed control has been disengaged,
depressing the ACCEL switch restores the vehicle to
the target speed that was stored in the PCM's RAM.
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 pro-
grammed for an acceleration feature. With the
ACCEL switch held closed, the vehicle accelerates
slowly to the desired speed. The new target speed is
stored in the PCM's RAM when the ACCEL switch is
SPEED CONTROL
system. The steering-wheel-
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