DTC P0704 6.6L/LB7
Circuit Description
Battery voltage is supplied from the brake 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.
When the engine control module (ECM) detects a large number of gear changes without detecting a clutch switch transition, DTC P0704 sets. DTC P0704 is a type C DTC.
Conditions for Running the DTC
No VSS DTC P0500.
Conditions for Setting the DTC
The ECM detects 7 changes in vehicle speed from 0 km/h (0 mph) to above 38 km/h (24 mph) and then back to 0 km/h (0 mph) without the ECM detecting a clutch pedal transition.
Action Taken When the DTC Sets
| • | The ECM does not illuminate the malfunction indicator lamp (MIL). |
| • | The ECM disables cruise control. |
| • | The ECM disables power take-off. |
| • | The ECM records the operating conditions when the Conditions for Setting the DTC are met. The ECM records this information as Freeze Frame and Failure Records. |
| • | The ECM stores DTC P0704 in ECM history. |
Conditions for Clearing the MIL/DTC
| • | A scan tool can clear the MIL/DTC. |
| • | The ECM clears the DTC from ECM history if the vehicle completes 40 warm-up cycles without an emission-related diagnostic fault occurring. |
| • | The ECM cancels the DTC default actions when the ignition switch is OFF long enough in order to power down the ECM. |
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 - 6.6L (LB7) |
2 |
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 - 6.6L (LB7) | Go to Step 3 |
3 | Inspect the adjustment of the clutch pedal position switch. Refer to Clutch Pedal Position Switch Replacement in Clutch. Did you find and correct a condition? | -- | Go to Step 14 | Go to Step 4 |
4 |
Caution: Refer to SIR Caution in the Preface section. Does the DMM indicate the specified value? | B+ | Go to Step 5 | Go to Step 11 |
5 |
Does the scan tool display that the clutch is released? | -- | Go to Step 8 | Go to Step 6 |
6 |
Did you detect continuity? | -- | Go to Step 7 | Go to Step 10 |
7 | Use the DMM in order to test for continuity between Pin A of the clutch pedal position switch and ground. Refer to Testing for Continuity in Wiring Systems. Did you detect continuity? | -- | Go to Step 10 | Go to Step 9 |
8 |
Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 12 |
9 |
Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 13 |
10 | Repair the open or short to ground in the clutch position switch signal circuit. Refer to Wiring Repairs in Wiring Systems. Is the action complete? | -- | Go to Step 14 | -- |
11 | Repair the open in the clutch position switch feed circuit. Refer to Wiring Repairs in Wiring Systems. Is the action complete? | -- | Go to Step 14 | -- |
12 | Replace the clutch pedal position switch. Refer to Clutch Pedal Position Switch Replacement in Clutch. Is the action complete? | -- | Go to Step 14 | -- |
13 | Replace the ECM. Refer to Engine Control Module Replacement in Engine Controls - 6.6L (LB7). Is the action complete? | -- | Go to Step 14 | -- |
14 |
Has the test run and passed? | -- | Go to Step 15 | Go to Step 2 |
15 | 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 - 6.6L (LB7) | System OK |
