Pinpoint Test F : Shift Fork Actuator - Electrical Fault
- Refer to Transmission Controls - DPS6
for schematic and connector information.
Normal Operation and Fault Conditions
The shift system consists of two independent sub-systems controlling the transmission synchronizer pre-selections and engagements. This arrangement provides independent control of the two transmission and a mechanical interlock that prevents two gears within the same transmission from being engaged simultaneously. The TCM contains two electric motors that mesh with and drive the first double gear wheel, which drives the second double gear which finally drives the shift drum. Gearing between the shift motors and the drums reduce speed and multiply torque. Position sensors in the TCM detect motor position. Shift drum position is learned by the TCM during a teach-in process that involves rotating each drum.
DTC Fault Trigger Conditions
DTC Description Fault Trigger Condition TCM P2831:00 Shift Fork "A" Position Circuit: No Sub Type Information Shift drum motor 1 fault detected. TCM P2832:00 Shift Fork "A" Position Circuit Range/Performance: No Sub Type Information TCM found an error with shift drum 1 that indicated it has lost position. TCM P2835:00 Shift Fork "A" Position Circuit Intermittent: No Sub Type Information Shift drum motor 1 sequence fault detected. TCM P2836:00 Shift Fork "B" Position Circuit: No Sub Type Information Shift drum motor 2 fault detected. TCM P2837:00 Shift Fork "B" Position Circuit Range/Performance: No Sub Type Information TCM found an error with shift drum 2 that indicated it has lost position. TCM P283A:00 Shift Fork "B" Position Circuit Intermittent: No Sub Type Information Shift drum motor 2 sequence fault detected. TCM P285B:00 Shift Fork "A" Actuator Circuit/Open: No Sub Type Information Shift drum motor 1 open circuit fault detected. TCM P285C:00 Shift Fork "A" Actuator Performance: No Sub Type Information This DTC sets with P285B, P285D and/or P285E. Used to light the wrench lamp. TCM P285D:00 Shift Fork "A" Actuator Circuit Low: No Sub Type Information Shift drum motor 1 short to ground fault detected. TCM P285E:00 Shift Fork "A" Actuator Circuit High: No Sub Type Information Shift drum motor 1 short to power fault detected. TCM P285F:00 Shift Fork "B" Actuator Circuit/Open: No Sub Type Information Shift drum motor 2 open circuit fault detected. TCM P2860:00 Shift Fork "B" Actuator Performance: No Sub Type Information This DTC sets with P285F, P2861 and/or P2862. Used to light the wrench lamp. TCM P2861:00 Shift Fork "B" Actuator Circuit Low: No Sub Type Information Shift drum motor 2 short to ground fault detected. TCM P2862:00 Shift Fork "B" Actuator Circuit High: No Sub Type Information Shift drum motor 2 short to power fault detected. Possible Sources
- Connectors damaged or pushed-out terminals, corrosion, loose wires and missing or damaged seals
- Shift drum motor 1
- Shift drum motor 2
- TCM
- F1 READ AND RECORD ALL DTCS
- Using the diagnostic scan tool, retrieve all DTCs.
Are System Voltage DTCs present?
Yes GO to Pinpoint Test H No GO to F2 - F2 CHECK FOR SHIFT FORK DIAGNOSTIC TROUBLE CODES (DTCS)
- Using the diagnostic scan tool, retrieve all DTCs.
Are Shift Fork electrical DTCs present?
Yes CARRY OUT the Shift Drum Adaptive Learning. REFER to: Transmission Control Module (TCM) Adaptive Learning . If the shift fork electrical DTCs return, INSTALL a new TCM. REFER to: Transmission Control Module (TCM) . No GO to Pinpoint Test G