Pinpoint Test I : Line Pressure Control (LPC) Solenoid

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.

I1 RETRIEVE AND RECORD ALL DTCS
- Using the diagnostic scan tool, retrieve all DTCs.
Are DTCs P0748, P0960, P0961, P0962 and/or P0963 present?

Yes For DTCs P0748 and P0960, GO to I2 For DTCs P0748, P0961 and P0962, GO to I5 For DTCs P0748 and P0963, GO to I7

No REFER to: Diagnosis By Symptom .

I2 CHECK THE LINE PRESSURE CONTROL (LPC) SOLENOID CONTROL CIRCUIT FOR AN OPEN

Ignition OFF.

Disconnect Transmission Vehicle Harness C1520A.

Disconnect PCM C1381E.

Inspect the connectors for damaged or pushed-out terminals, corrosion, loose wires and missing or damaged seals.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C1520A-3	Courtesy of FORD MOTOR COMPANY	C1381E-59

Is the resistance less than 3 ohms?

Yes

GO to I3

No	REPAIR the circuit.

I3 CHECK THE LINE PRESSURE CONTROL (LPC) SOLENOID FOR AN OPEN

Measure:

Positive Lead	Measurement / Action	Negative Lead
Component side resistance pin 5.	Courtesy of FORD MOTOR COMPANY	Component side resistance pin 3.

Is the resistance between 4.0 and 7.2 ohms?

Yes	Refer to PCM GUIDED ROUTINE TESTING

GO to I4

I4 CHECK THE LINE PRESSURE CONTROL (LPC) SOLENOID RESISTANCE

Remove the transmission internal wiring harness frame. REFER to: Transmission Internal Wiring Harness Frame . Inspect for metal shavings on the exposed metal contacts or other components and clean the solenoid and transmission internal wiring harness frame terminals.

Measure:

Positive Lead	Measurement / Action	Negative Lead
LPC Solenoid pin A.	Courtesy of FORD MOTOR COMPANY	LPC Solenoid pin B.

Is the resistance between 4.0 and 7.2 ohms?

Yes	INSTALL a new transmission internal wiring harness frame. REFER to: Transmission Internal Wiring Harness Frame .

No	INSTALL a new LPC solenoid. REFER to: Solenoid .

I5 CHECK THE LINE PRESSURE CONTROL (LPC) SOLENOID CONTROL CIRCUIT FOR A SHORT TO GROUND

Ignition OFF.

Disconnect Transmission Vehicle Harness C1520A.

Disconnect PCM C1381E.

Inspect the connectors for damaged or pushed-out terminals, corrosion, loose wires and missing or damaged seals.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C1520A-3	Courtesy of FORD MOTOR COMPANY	Ground

Is the resistance greater than 10, 000 ohms?

Yes

GO to I6

No	REPAIR the circuit.

I6 CHECK THE LINE PRESSURE CONTROL (LPC) SOLENOID FOR A SHORT TO GROUND

Remove the transmission internal wiring harness frame. REFER to: Transmission Internal Wiring Harness Frame . Inspect for metal shavings on the exposed metal contacts or other components and clean the solenoid and transmission internal wiring harness frame terminals.

Measure:

Positive Lead	Measurement / Action	Negative Lead
LPC Solenoid pin A.	Courtesy of FORD MOTOR COMPANY	Ground

Is the resistance less than 3 ohms?

Yes	INSTALL a new LPC solenoid. REFER to: Solenoid .

No	INSTALL a new transmission internal wiring harness frame. REFER to: Transmission Internal Wiring Harness Frame .

I7 CHECK THE LINE PRESSURE CONTROL SOLENOID (LPC) FOR A SHORT TO VOLTAGE

Ignition OFF.

Disconnect Transmission Vehicle Harness C1520A.

Disconnect PCM C1381E.

Inspect the connectors for damaged or pushed-out terminals, corrosion, loose wires and missing or damaged seals.

Ignition ON.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C1520A-3	Courtesy of FORD MOTOR COMPANY	Ground

Is any voltage present?

Yes	REPAIR the circuit.

No	Refer to PCM GUIDED ROUTINE TESTING