Circuit Description
Battery voltage is supplied from the ABS fuse to the clutch switch. The clutch switch is a normally closed switch. When the clutch pedal is released, the clutch pedal position switch signal circuit is pulled up to B+. When the clutch pedal is applied, the switch opens, and the voltage drops to 0 volts.
If the powertrain control module (PCM) detects a specified number of vehicle speed transitions without detecting a clutch switch transition, DTC P0704 will set. DTC P0704 is a type C DTC.
Conditions for Running the DTC
No vehicle speed sensor (VSS) DTC P0500.
Conditions for Setting the DTC
The PCM detects 7 changes in vehicle speed 0- 38 km/h (0-24 mph) without the PCM detecting a clutch pedal transition.
Action Taken When the DTC Sets
| • | The PCM will not illuminate the malfunction indicator lamp (MIL). |
| • | The PCM disables cruise control. |
| • | The PCM records the operating conditions when the Conditions for Setting the DTC are met. The PCM records this information as Failure Records. |
| • | The PCM stores DTC P0704 in PCM history. |
Conditions for Clearing the DTC
| • | A scan tool can clear the DTC. |
| • | The PCM cancels the DTC default actions when the ignition switch is OFF long enough in order to power down the PCM. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are present by this diagnostic or any other emission-related diagnostic. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This test confirms if the scan tool is receiving a clutch switch position signal.
-
This step inspects the clutch pedal connector and adjustment.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Diagnostic System Check - Engine Controls? | -- | Go to Step 2 | Go to Diagnostic System Check - Engine Controls in Engine Controls - 4.3L |
Does the scan tool indicate a change in state when the clutch pedal is either applied or released? | -- | Go to Intermittent Conditions in Engine Controls - 4.3L | Go to Step 3 | |
Inspect the adjustment of the clutch pedal position switch and the connector. Does the clutch switch require adjustment or the connector require service? | -- | Go to Step 11 | Go to Step 4 | |
4 | Inspect the ABS fuse for an open. Refer to Circuit Protection - Fuses in Wiring Systems. Is the ABS fuse open? | -- | Go to Step 9 | Go to Step 5 |
5 | Using a DMM, measure voltage at the brake fuse. Does the DMM indicate the specified value? | B+ | Go to Step 6 | Go to Step 12 |
6 |
Does the DMM indicate the specified value? | B+ | Go to Step 7 | Go to Step 13 |
7 |
Does the scan tool display that the clutch is applying and releasing? | -- | Go to Step 15 | Go to Step 8 |
8 |
Did you find a short to voltage, high resistance or an open on the clutch pedal position switch signal circuit? | -- | Go to Step 14 | Go to Step 16 |
9 |
Is the ignition 3 voltage circuit grounded? | -- | Go to Step 13 | Go to Step 10 |
10 | Using a DMM, test for a short to ground on the clutch pedal position switch signal circuit at the switch connector. Is the clutch pedal position switch signal circuit grounded? | -- | Go to Step 14 | Go to Step 15 |
11 | Adjust the clutch pedal position switch or repair the connector as necessary. Did you complete the repair? | -- | Go to Step 17 | -- |
12 | Repair the power distribution circuit to the brake fuse. Did you complete the repair? | -- | Go to Step 17 | -- |
13 | Repair the open, high resistance or short to ground in the ignition 3 voltage circuit or a parallel circuit that uses the brake fuse. Did you complete the repair? | -- | Go to Step 17 | -- |
14 | Repair the open, high resistance or short to ground in the clutch pedal position switch signal circuit. Did you complete the repair? | -- | Go to Step 17 | -- |
15 | Replace the clutch pedal position switch. Is the action complete? | -- | Go to Step 17 | -- |
16 | Replace the PCM. Refer to Powertrain Control Module Replacement in Engine Controls - 4.3L. Is the action complete? | -- | Go to Step 17 | -- |
17 |
Has the test run and passed? | -- | System OK | Go to Step 2 |
18 | With the scan tool, observe the stored information, capture info and DTC info. Does the scan tool display any DTCs that you have not diagnosed? | -- | Go to Diagnostic Trouble Code (DTC) List in Engine Controls - 4.3L | System OK |
