Circuit Description
If the PCM is allowing cruise operation and the customer requests cruise, the cruise control module will send a cruise engaged signal (CKT 396) to the PCM. This diagnostic test will set if the cruise control is engaged and the transaxle pressure switch is indicating that the transaxle is in PARK or NEUTRAL. It is a protective measure to disengage cruise when the vehicle is shifted out of a drive gear while the cruise is engaged.
Conditions for Running the DTC
| • | Cruise control enabled. |
| • | Cruise control engaged. |
Conditions for Setting the DTC
Transaxle pressure switch (TFP) input to the PCM indicating transaxle in PARK or NEUTRAL.
Action Taken When the DTC Sets
PCM disables cruise control.
| • | The Malfunction Indicator Lamp (MIL) will not illuminate. |
| • | No message will be displayed. |
Conditions for Clearing the DTC
| • | A History DTC will clear after forty consecutive warm-up cycles with no failures of any non-emission related diagnostic test. |
| • | A Last Test Failed (current) DTC will clear when the diagnostic runs and does not fail. |
| • | Use a scan tool to clear DTCs. |
| • | Interrupting PCM battery voltage may or may not clear DTCs. This practice is not recommended. Refer to Clearing Diagnostic Trouble Codes in PCM Description and Operation. |
Diagnostic Aids
Shifting into neutral while cruise control is engaged will set this DTC.
If this DTC was not induced by the driver use the Failure Records data on the scan tool to compare both the Trans Range Switch and the TFP switch to verify the driver did not induce this DTC. Compare both displays to see if the trans fluid pressure switch circuit may have an intermittent fault.
Clear the DTC and operate the vehicle under the conditions in which the DTC set if a fault condition is suspected.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | ||
2 | Connect the scan tool. Is DTC P1520, P1554 or P1810 also set? | -- | Diagnose those DTCs first | |
3 | Since this DTC will set when the vehicle is shifted into NEUTRAL or PARK while the cruise is engaged, check with the customer to verify the conditions under which the DTC set. Did the drivers actions cause this DTC to set? | -- | Refer to Diagnostic Aids | |
4 | Explain system operation to the customer and clear this DTC. Is the repair complete? | -- | System OK | -- |
