Pinpoint Test M : Transmission Fluid Auxiliary Pump: Notes
WARNING: This page is about a different car, the 2018 Ford Edge. However, it is still accessible from the selected car via links, so may be relevant.
Transmission Fluid Pump
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 Conditions |
|---|---|---|
| P0C27 | Electric Transmission Fluid Pump Motor Control Module | This DTC sets if the E-pump communication is OK. The frequency is between 130 Hz and 170 Hz but a low current is detected (10% to 15% duty cycle). |
| P0C28 | Electric Transmission Fluid Pump Motor Current Low | This DTC sets if the E-pump communication is OK. The frequency is between 130 Hz and 170 Hz but a low current is detected (20% to 25% duty cycle). |
| P0C29 | Electric Transmission Fluid Pump Motor Current High | This DTC sets if the E-pump communication is OK. The frequency is between 130 Hz and 170 Hz but a high current is detected. |
| P0C2A | Electric Transmission Fluid Pump Motor Stalled | This DTC sets if the PCM commands the electric transmission fluid pump motor on and does not detect a corresponding increase in pump pressure, indicating a stalled pump motor. |
| P0C2C | Electric Transmission Fluid Pump Control Module Feedback Signal Range/Performance | 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. |
| P0C2D | Electric Transmission Fluid Pump Control Module Feedback Signal Low | This DTC sets if the duty cycle is less than 10%. |
| P0C2E | Electric Transmission Fluid Pump Control Module Feedback Signal High | This DTC sets if the duty cycle is greater than 90%. |
| P175A | Transmission Fluid Over Temperature Condition - Electric Transmission Fluid Pump Disabled | This DTC sets if the E-pump communication is OK. The frequency is between 130 Hz and 170 Hz but an over temperature condition is detected (30% to 34% duty cycle). |
| P2796 | Electric Transmission Fluid Pump Control Circuit | 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