Pinpoint Test M : DTC P0C2C:00, P0C2D:00, P0C2E:00, P2796:00
- Refer to Auto-Start-Stop System
for schematic and connector information.
Normal Operation and Fault Conditions
The electronic transmission fluid auxiliary pump is used to keep the transmission engaged when the engine is stopped and the transmission is in drive. The electronic transmission fluid auxiliary pump has an internal microprocessor and communicates with the PCM over a PWM circuit with a frequency of 150 Hz with a duty cycle range of 10% to 90%.
DTC Fault Trigger Conditions
DTC Description Fault Trigger Condition PCM P0C2C:00 Electric Transmission Fluid Pump Control Module Feedback Signal Range/Performance: No Sub Type Information This DTC sets if the E-pump communication is OK. The frequency is between 130 Hz and 170 Hz but the duty cycle does not match one of the defined duty cycle ranges. PCM P0C2D:00 Electric Transmission Fluid Pump Control Module Feedback Signal Low: No Sub Type Information This DTC sets if the duty cycle is less than 10%. PCM P0C2E:00 Electric Transmission Fluid Pump Control Module Feedback Signal High: No Sub Type Information This DTC sets if the duty cycle is greater than 90%. PCM P2796:00 Electric Transmission Fluid Pump Control Circuit: No Sub Type Information This DTC sets when the E-pump is not receiving a signal on it's PWM input signal from the PCM. Possible Sources
- Connectors damaged or pushed-out terminals, corrosion, loose wires or ground and missing or damaged seals
- BJB fuse 72 (20A)
- BJB fuse 21 (15A)
- Transmission fluid auxiliary pump
- PCM
- M1 RETRIEVE AND RECORD ALL DTCS
- Using the diagnostic scan tool, retrieve all DTCs.
Are DTCs P0C2C:00, P0C2D:00, P0C2E:00, P2796:00 present?
Yes For DTC P2796, GO to M7 For all other DTCs, GO to M2 No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or terminal issues. - M2 CHECK THE TRANSMISSION FLUID AUXILIARY PUMP POWER CIRCUITS
- Ignition OFF.
- Disconnect Transmission Fluid Auxiliary Pump C1717.
- Ignition ON.
Is the voltage greater than 11 volts?
Yes GO to M3 No VERIFY the BJB fuses 72 (20A) and 21 (15A) are OK. If fuses are OK, REPAIR the affected circuit for an open. If fuses are not OK, REFER to OEM Electrical Wiring Diagram Introduction (Except Hybrid) to identify the cause of the affected circuit shorted to ground. - M3 CHECK THE TRANSMISSION FLUID AUXILIARY PUMP GROUND CIRCUIT FOR AN OPEN
- Measure:
Positive Lead Measurement / Action Negative Lead C1717-6 Ground
Is the resistance less than 3 ohms?
Yes GO to M4 No REPAIR the circuit - Measure:
- M4 CHECK TRANSMISSION FLUID AUXILIARY PUMP FEEDBACK / MONITOR CIRCUIT FOR OPEN
- Ignition OFF.
- Disconnect PCM C1551E.
Is the resistance less than 3 ohms?
Yes GO to M5 No REPAIR the circuit. - M5 CHECK TRANSMISSION FLUID AUXILIARY PUMP FEEDBACK / MONITOR CIRCUIT FOR SHORT TO GROUND
- Ignition OFF.
- Measure:
Positive Lead Measurement / Action Negative Lead C1551E-81 Ground
Is the resistance greater than 10, 000 ohms?
Yes GO to M6 No REPAIR the circuit - M6 CHECK TRANSMISSION FLUID AUXILIARY PUMP FEEDBACK / MONITOR CIRCUIT FOR SHORT TO POWER
- Ignition ON.
- Measure:
Positive Lead Measurement / Action Negative Lead C1717-5 Ground
Is any voltage detected?
Yes REPAIR the circuit. No GO to M7 - M7 CHECK TRANSMISSION FLUID AUXILIARY PUMP COMMAND CIRCUIT FOR SHORT TO POWER
- Ignition OFF.
- Disconnect PCM C1551E.
- Disconnect Transmission Fluid Auxiliary Pump C1717.
- Ignition ON.
- Measure:
Positive Lead Measurement / Action Negative Lead C1551E-79 Ground
Is any voltage detected?
Yes REPAIR the circuit. No GO to M8 - M8 CHECK TRANSMISSION FLUID AUXILIARY PUMP COMMAND CIRCUIT FOR OPEN
- Ignition OFF.
Is the resistance less than 3 ohms?
Yes GO to M9 No REPAIR the circuit - M9 CHECK THE TRANSMISSION FLUID AUXILIARY PUMP PWM (PULSE WIDTH MODULATION) CIRCUIT FOR A SHORT TO GROUND
- Measure:
Positive Lead Measurement / Action Negative Lead C1551E-79 Ground
Is the resistance greater than 10, 000 ohms?
Yes GO to M10 No REPAIR the circuit - Measure:
- M10 CHECK THE TRANSMISSION FLUID AUXILIARY PUMP DUTY CYCLE OPERATION
- Connect PCM C1551E.
- Connect Transmission Fluid Auxiliary Pump C1717.
- Connect the diagnostic tool.
- Ignition ON.
- Using a diagnostic scan tool, COMMAND the transmission fluid auxiliary pump ON using PID, TRANS_PMP_CMD and vary the duty cycle from 20% to 90%,
Is the transmission fluid auxiliary pump operating and does the pump speed change as the duty cycle is increased or decreased?
Yes The transmission fluid auxiliary pump is operating correctly at this time. No INSTALL a new transmission fluid auxiliary pump. REFER to: Transmission Fluid Auxiliary Pump .