GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1999 🢒 Corvette 🢒 Body and Accessories 🢒 Cruise Control 🢒 Does Not Resume, Accelerate,or Tap Up or Down

Does Not Resume, Accelerate, Tap Up, or Down

Step

Action

Value(s)

Yes

No

1

Has the Cruise Control System Check been performed?

--

Go to Step 2

Go to Cruise Control System Check

2

Install a scan tool and display the PCM DTCs.

Are any cruise control related DTCs displayed? Refer to Diagnostic Trouble Code (DTC) List/Type .

--

Go to applicable DTC diagnostic routine

Go to Step 3

3
  1. Turn the ignition switch on.
  2. Display the PCM inputs, cruise control, data display list.
  3. Turn the cruise switch ON.

Does the scan tool indicate the cruise switch is on?

--

Go to Step 4

Go to Step 8

4

Press the cruise switch to the R/A position.

Does the scan tool indicate the cruise resume/accel switch is on?

--

Go to Step 5

Go to Step 22

5

With the cruise switch in the on position, press the Set switch.

Does the scan tool indicate the set/coast switch is on?

--

Go to Step 6

Go to Step 23

6

Press and release the brake pedal.

Does the scan tool indicate the TCC/CC brake switch, and the stoplamp switch applied and released?

--

Go to Step 7

Go to DTC P0571 Cruise Control Brake Switch Circuit or DTC P1574 Stoplamp Switch Circuit

7

With MT press and release the clutch pedal.

Does the scan tool indicate the clutch switch depressed and released?

--

Go to Cruise Control System Check

Go to DTC P0704 Clutch Switch Circuit

8

Inspect the CR CONT fuse #20 for an open.

Is the fuse open?

--

Go to Step 9

Go to Step 20

9
  1. Remove the CR CONT fuse #20.
  2. Connect a DMM from the fuse terminal A, in the instrument panel electrical center, to ground.
  3. With the cruise switch in the off position, measure the resistance to ground of circuit 1239.

Is circuit 1239 shorted to ground?

--

Go to Step 16

Go to Step 10

10
  1. Disconnect the TAC module connector C2.
  2. With the DMM connected as in the previous step, turn the cruise switch to the on position.

Is the resistance the specified value?

Infinite

Go to Step 13

Go to Step 11

11
  1. With the TAC module connector C2 disconnected, and the DMM connected as in the previous step.
  2. Press the cruise switch to the R/A position.

Is the resistance the specified value?

Infinite

Go to Step 14

Go to Step 12

12
  1. With the TAC module connector disconnected, and the DMM connected as in the previous step.
  2. With the cruise switch in the on position, press the Set switch.

Is the resistance the specified value?

Infinite

Go to Step 15

System ok

13
  1. Disconnect the multifunction switch connector C217.
  2. Connect a DMM from the switch side connector C217 terminal B to ground.
  3. Turn the cruise switch to the on position.
  4. Measure the resistance to ground of circuit 397 through the switch.

Is the resistance within specified values?

Infinite

Go to Step 17

Go to Step 27

14
  1. Disconnect the multifunction switch connector C217.
  2. Connect a DMM from the switch side connector C217 terminal B to ground.
  3. Press the cruise switch to the R/A position.
  4. Measure the resistance to ground of circuit 87 through the switch.

Is the resistance within specified values?

Infinite

Go to Step 18

Go to Step 27

15
  1. Disconnect the multifunction switch connector C217.
  2. Connect a DMM from the switch side connector C217 terminal B to ground.
  3. Turn the cruise switch to the on position.
  4. Press the Set switch.
  5. Measure the resistance to ground of circuit 84 through the switch.

Is the resistance within specified values?

Infinite

Go to Step 19

Go to Step 27

16

Repair the short to ground in circuit 1239.

Is the repair complete?

--

Go to Cruise Control System Check

--

17

Inspect and repair the short to ground in circuit 397. If ok replace the TAC module. Refer to Powertrain Control Module/Throttle Actuator Control Module Replacement .

Is the repair complete?

--

Go to Cruise Control System Check

--

18

Inspect and repair the short to ground in circuit 87. If ok replace the TAC module. Refer to Powertrain Control Module/Throttle Actuator Control Module Replacement .

Is the repair complete?

--

Go to Cruise Control System Check

--

19

Inspect and repair the short to ground in circuit 84. If ok replace the TAC module. Refer to Powertrain Control Module/Throttle Actuator Control Module Replacement .

Is the repair complete?

--

Go to Cruise Control System Check

--

20
  1. Disconnect the multifunction switch connector C217.
  2. Connect a test light from the harness side connector C217 terminal B to ground.

Does the test light illuminate?

--

Go to Step 21

Go to Step 28

21
  1. Connect a DMM from the switch side connector C217 terminal B to A.
  2. Turn the cruise switch to the on position.
  3. Measure the resistance of circuit 397 through the switch.

Is the resistance within specified values?

0-2 ohms

Go to Step 24

Go to Step 27

22
  1. Disconnect the multifunction switch connector C217.
  2. Connect a DMM from the switch side connector C217 terminal B to D.
  3. Press the cruise switch to the R/A position.
  4. Measure the resistance to circuit 87 through the switch.

Is the resistance within specified values?

0-2 ohms

Go to Step 25

Go to Step 27

23
  1. Disconnect the multifunction switch connector C217.
  2. Connect a DMM from the switch side connector C217 terminal B to C.
  3. Turn the cruise switch to the on position.
  4. Press the Set switch.
  5. Measure the resistance of circuit 84 through the switch.

Is the resistance within specified values?

0-2 ohms

Go to Step 26

Go to Step 27

24

Inspect and repair the open or high resistance in circuit 397. If ok replace the TAC module. Refer to Powertrain Control Module/Throttle Actuator Control Module Replacement .

Is the repair complete?

--

Go to Cruise Control System Check

--

25

Inspect and repair the open or high resistance in circuit 87. If ok replace the TAC module. Refer to Powertrain Control Module/Throttle Actuator Control Module Replacement .

Is the repair complete?

--

Go to Cruise Control System Check

--

26

Inspect and repair the open or high resistance in circuit 84. If ok replace the TAC module. Refer to Powertrain Control Module/Throttle Actuator Control Module Replacement .

Is the repair complete?

--

Go to Cruise Control System Check

--

27

Replace the multifunction switch. Refer to Multifunction Turn Signal Lever Replacement - On Vehicle .

Is the repair complete?

--

Go to Cruise Control System Check

--

28

Repair the open or high resistance in circuit 1239.

Is the repair complete?

--

Go to Cruise Control System Check

--