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Set/Coast Switch Test

  1. Turn ignition switch on. Place cruise control switch in "ON" position. Measure voltage at control module by probing pin "L" (circuit 84) and connecting other end of voltmeter to ground. If 12 volts are present, go to step 2). If no voltage is present, got to step 4).
  2. Disconnect control module connector. Probe pin "L" (circuit 84) and other end of voltmeter to ground. If voltage is zero, check circuit 84 shorting to 12 volts in connector or malfunctioning control module. Repair or replace as necessary.
  3. If 12 volts are present, disconnect connector (C235) and measure voltage at terminal "D" (circuit 84) on switch side of connector. If voltage is zero, check for short to 12 volts in wire. Repair or replace as necessary. If 12 volts are present, check for short in (C235) connector. If no short, replace switch. Check for proper system operation.
  4. Depress and hold in set/coast switch. Measure voltage at pin "L" (circuit 84) of control module. If 12 volts are present, switch is okay. If voltage is zero, disconnect connector (C235) and measure voltage at terminal "B" (circuit 397) on switch side of connector.
  5. If voltage is zero, go to step 7). If 12 volts are present, depress and hold in set/coast switch. Measure voltage at terminal "D" on switch side of connector. If voltage is zero, replace switch.
  6. If 12 volts are present, check terminal "D" (circuit 84) of connector (C235) to pin "L" of control module. Locate open in circuit, repair and replace as necessary. Check for proper system operation.
  7. Measure voltage at terminal "A" (circuit 39) on harness connector side. If voltage is zero, locate open in circuit 39 or blown fuse. Repair or replace as necessary.
  8. If 12 volts are present, ensure that cruise control switch is in "ON" position. If switch is on and zero volts are present at terminal "B" (circuit 397) on connector side of switch, replace switch.
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