Pinpoint Test A: Gear Shift Position Sensor Circuit Faults

WARNING: This page is about a different variant/trim than selected.

NOTE: The gear shift position sensor is also know as the rev matching / selected gear / neutral position sensor.

Refer to ELECTRONIC ENGINE CONTROLS - 5.0L for schematic and connector information.

Normal Operation and Fault Conditions

The transmission gear shift position sensor is bolted to the transmission housing and detects the position of a magnet mounted on the gear selector shaft. The gear shift position sensor provides 3 PWM (pulse width modulation) output signals. The TR_NEUTRAL_RAW and TR_NTRL_RAW2 signals both indicate the gear selector shaft axial position and if the selected gear is odd, even, or neutral. The two separate signals provide redundancy to ensure safe detection of the gear engagement status. The GEAR_SHIFT_C_DC signal indicates shaft rotation and which shift fork is selected. The PCM (Power Control Module) interprets these signals to determine the selected gear. The PCM PID GEARPOS_MAN indicates the selected gear as NEUTRAL, 1, 2, 3, 4, 5, 6, or REVERSE. As a rationality check, the PCM compares the selected gear detected to the calculated transmission gear ratio using vehicle and engine speed when the clutch pedal is fully released.

This data is used for several vehicle features and functions including IPC gear indication, hill start assist, and rev matching features. The rev matching function allows the PCM to target an engine speed to match the resultant input speed of the transmission based on the gear shifter position. The rev matching function is provided to lessen the engine braking force the driver and passengers feel on a downshift. The rev matching function can be turned on and off using the information display menu.

The gear shift position sensor includes a 6 pin electrical connector. The PCM provides a 5 volt VREF signal on pin 1 and SIGNAL RETURN on pin 6. VREF is shared with the particulate filter pressure sensors, if equipped. SIGNAL RETURN is shared with the clutch master cylinder push rod position sensor. The sensor outputs TR_NEUTRAL_RAW on pin 2, GEAR_SHIFT_C_DC on pin 3, and TR_NTRL_RAW2 on pin 4. Pin 5 is not used in this application.

To achieve the required accuracy for the safe operation of these features the sensors need to be programmed to the characteristics of each individual magnet on the gear selector shaft. Once programmed, it is not possible to reprogram or otherwise adjust a sensor. The sensor and magnet must always be installed together as a matched pair.

DTC Fault Trigger Conditions

DTC	Description	Fault Trigger Condition
PCM P086B:00	Neutral Position Sensor 'A' Circuit Range/Performance: No Sub Type Information	This DTC sets when the raw neutral position sensor "A" frequency output from the gear shift position sensor is out of range for the pulse-width modulated signal. This is likely due to a circuit fault (open, short to ground, short to power) or an internal sensor fault. TR_NTRL_A_FRQ is less than 225 Hz or greater than 275 Hz when measured by the PCM at C175T-36
PCM P086C:00	Neutral Position Sensor 'A' Circuit Low: No Sub Type Information	This DTC sets when the raw neutral position sensor \"A\" duty cycle output from the gear shift position sensor is out of range for the pulse-width modulated signal. This is likely due to a circuit fault (open, short to ground, short to power), an internal sensor fault, or a missing target magnet. TR_NEUTRAL_RAW is less than 7% when measured by the PCM at C175T-36
PCM P086D:00	Neutral Position Sensor 'A' Circuit High: No Sub Type Information	This DTC sets when the raw neutral position sensor \"A\" duty cycle output from the gear shift position sensor is out of range for the pulse-width modulated signal. This is likely due to a circuit fault (open, short to ground, short to power) or an internal sensor fault. TR_NEUTRAL_RAW is greater than 93% when measured by the PCM at C175T-36
PCM P08AE:00	Neutral Position Sensor 'B' Circuit Range/Performance: No Sub Type Information	This DTC sets when the raw neutral position sensor "B" frequency output from the gear shift position sensor is out of range for the pulse-width modulated signal. This is likely due to a circuit fault (open, short to ground, short to power) or an internal sensor fault. TR_NTRL_B_FRQ is less than 225 Hz or greater than 275 Hz when measured by the PCM at C175T-38
PCM P08AF:00	Neutral Position Sensor 'B' Circuit Low: No Sub Type Information	This DTC sets when the raw neutral position sensor \"B\" duty cycle output from the gear shift position sensor is out of range for the pulse-width modulated signal. This is likely due to a circuit fault (open, short to ground, short to power), an internal sensor fault, or a missing target magnet. TR_NTRL_RAW2 is less than 7% when measured by the PCM at C175T-38
PCM P08B0:00	Neutral Position Sensor 'B' Circuit High: No Sub Type Information	This DTC sets when the raw neutral position sensor \"B\" duty cycle output from the gear shift position sensor is out of range for the pulse-width modulated signal. This is likely due to a circuit fault (open, short to ground, short to power) or an internal sensor fault. TR_NTRL_RAW2 is greater than 93% when measured by the PCM at C175T-38
PCM P095A:00	Gear Shift Position Circuit 'C': No Sub Type Information	This DTC sets when the raw neutral position sensor "C" frequency output from the gear shift position sensor is out of range for the pulse-width modulated signal. This is likely due to a circuit fault (open, short to ground, short to power) or an internal sensor fault. GEAR_SHIFT_C_FRQ is less than 225 Hz or greater than 275 Hz when measured by the PCM at C175T-39
PCM P095C:00	Gear Shift Position Circuit 'C' Low: No Sub Type Information	This DTC sets when the raw neutral position sensor \"C\" duty cycle output from the gear shift position sensor is out of range for the pulse-width modulated signal. This is likely due to a circuit fault (open, short to ground, short to power), an internal sensor fault, or a missing target magnet. GEAR_SHIFT_C_FRQ is less than 10% when measured by the PCM at C175T-39
PCM P095D:00	Gear Shift Position Circuit 'C' High: No Sub Type Information	This DTC sets when the raw neutral position sensor \"C\" duty cycle output from the gear shift position sensor is out of range for the pulse-width modulated signal. This is likely due to a circuit fault (open, short to ground, short to power) or an internal sensor fault. GEAR_SHIFT_C_FRQ is greater than 90% when measured by the PCM at C175T-39

Possible Sources

Gear shift position sensor loose or damaged
Gear shift position sensor internal fault
Gear shift position sensor target magnet dislodged, missing, out of proximity to the sensor
PCM
Wiring, terminals or connectors

Visual Inspection and Pre-checks

Gear shift position sensor
Gear shift position sensor connector

A1 CHECK THE GEAR SHIFT POSITION SENSOR
- Visually inspect the gear shift position sensor and connector for obvious signs of damage.
Were any conditions found during inspection?

Yes REPAIR as necessary.

No GO to A2

A2 CHECK THE GEAR SHIFT POSITION SENSOR CIRCUITS FOR SHORTS TO VOLTAGE

Ignition OFF.

Disconnect PCM C175T .

Disconnect gear shift position sensor C1854 .

Disconnect clutch master cylinder push rod position sensor C2478 .

Disconnect particulate filter pressure sensor 11 C1422, if equipped.

Disconnect particulate filter pressure sensor 21 C1421, if equipped.

Ignition ON.

Measure:

Positive Lead	Measurement / Action	Negative Lead
VREF C1854-1	Courtesy of FORD MOTOR COMPANY	Ground
Gear shift position sensor "A" C1854-2	Courtesy of FORD MOTOR COMPANY	Ground
Gear shift position sensor "C" C1854-3	Courtesy of FORD MOTOR COMPANY	Ground
Gear shift position sensor "B" C1854-4	Courtesy of FORD MOTOR COMPANY	Ground
SIGNAL RETURN C1854-6	Courtesy of FORD MOTOR COMPANY	Ground

Is any voltage present?

Yes	REPAIR the short to voltage.

GO to A3

A3 CHECK THE GEAR SHIFT POSITION SENSOR CIRCUITS FOR SHORTS TO GROUND

Ignition OFF.

Measure:

Positive Lead	Measurement / Action	Negative Lead
VREF C1854-1	Courtesy of FORD MOTOR COMPANY	Ground
Gear shift position sensor "A" C1854-2	Courtesy of FORD MOTOR COMPANY	Ground
Gear shift position sensor "C" C1854-3	Courtesy of FORD MOTOR COMPANY	Ground
Gear shift position sensor "B" C1854-4	Courtesy of FORD MOTOR COMPANY	Ground
SIGNAL RETURN C1854-6	Courtesy of FORD MOTOR COMPANY	Ground

Are the resistances greater than 10, 000 ohms?

Yes

GO to A4

No	REPAIR the short to ground.

A4 CHECK THE GEAR SHIFT POSITION SENSOR CIRCUITS FOR OPENS

Measure:

Positive Lead	Measurement / Action	Negative Lead
VREF C1854-1	Courtesy of FORD MOTOR COMPANY	C175T-81
Gear shift position sensor "A" C1854-2	Courtesy of FORD MOTOR COMPANY	C175T-36
Gear shift position sensor "C" C1854-3	Courtesy of FORD MOTOR COMPANY	C175T-39
Gear shift position sensor "B" C1854-4	Courtesy of FORD MOTOR COMPANY	C175T-38
SIGNAL RETURN C1854-6	Courtesy of FORD MOTOR COMPANY	C175T-7

Are the resistances less than 3 ohms?

Yes

GO to A5

No	REPAIR the open circuit.

A5 CHECK THE GEAR SHIFT POSITION SENSOR REFERENCE VOLTAGE CIRCUIT

Ignition OFF.

Connect PCM C175T .

Connect clutch master cylinder push rod position sensor C2478 .

Connect particulate filter pressure sensor 11 C1422, if equipped.

Connect particulate filter pressure sensor 21 C1421, if equipped.

Disconnect gear shift position sensor C1854 .

Ignition ON.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C1854-1	Courtesy of FORD MOTOR COMPANY	Ground

Is the voltage between 4.8 and 5.2 volts?

Yes

GO to A6

GO to A15

A6 CHECK THE GEAR SHIFT POSITION SENSOR GROUND CIRCUIT

Measure:

Positive Lead	Measurement / Action	Negative Lead
C1854-1	Courtesy of FORD MOTOR COMPANY	C1854-6

Is the voltage between 4.8 and 5.2 volts?

Yes

GO to A7

GO to A15

A7 CHECK THE GEAR SHIFT POSITION SENSOR FOR CORRECT OPERATION IN NEUTRAL

Start engine and allow to idle.

Engage parking brake.

Press and hold the clutch pedal for the duration of this test.

Position the gear shift lever in Neutral. Remove hand from gear shift lever

Access the PCM and monitor the gear shift position sensor data.

PID	Lower Limit	Upper Limit
TR_NEUTRAL_RAW	45 %	55 %
TR_NTRL_RAW2	36.3 %	43.7 %
GEAR_SHIFT_C_DC	51.3 %	68.7 %
TR_NTRL_A_FRQ	225 Hz	275 Hz
TR_NTRL_B_FRQ
GEAR_SHIFT_C_FRQ

Are all of the PID values within the limits?

Yes

GO to A8

No	INSTALL a new gear shift position sensor and magnet as a matched pair. REFER to: Gear Shift Position Sensor

A8 CHECK THE GEAR SHIFT POSITION SENSOR FOR CORRECT OPERATION IN FIRST GEAR

Start engine and allow to idle.

Engage parking brake.

Press and hold the clutch pedal for the duration of this test.

Position the gear shift lever in first gear. Remove hand from gear shift lever.

Access the PCM and monitor the gear shift position sensor data.

PID	Lower Limit	Upper Limit
TR_NEUTRAL_RAW	73.1 %	86.9 %
TR_NTRL_RAW2	56.7 %	68.3 %
GEAR_SHIFT_C_DC	31.3 %	48.7 %

Are all of the PID values within the limits?

Yes

GO to A9

No	INSTALL a new gear shift position sensor and magnet as a matched pair. REFER to: Gear Shift Position Sensor

A9 CHECK THE GEAR SHIFT POSITION SENSOR FOR CORRECT OPERATION IN SECOND GEAR

Start engine and allow to idle.

Engage parking brake.

Press and hold the clutch pedal for the duration of this test.

Position the gear shift lever in second gear. Remove hand from gear shift lever.

Access the PCM and monitor the gear shift position sensor data.

PID	Lower Limit	Upper Limit
TR_NEUTRAL_RAW	13.1 %	26.9 %
TR_NTRL_RAW2	11.7 %	23.3 %
GEAR_SHIFT_C_DC	31.3 %	48.7 %

Are all of the PID values within the limits?

Yes

GO to A10

No	INSTALL a new gear shift position sensor and magnet as a matched pair. REFER to: Gear Shift Position Sensor

A10 CHECK THE GEAR SHIFT POSITION SENSOR FOR CORRECT OPERATION IN THIRD GEAR

Start engine and allow to idle.

Engage parking brake.

Press and hold the clutch pedal for the duration of this test.

Position the gear shift lever in third gear. Remove hand from gear shift lever.

Access the PCM and monitor the gear shift position sensor data.

PID	Lower Limit	Upper Limit
TR_NEUTRAL_RAW	73.1 %	86.9 %
TR_NTRL_RAW2	56.7 %	68.3 %
GEAR_SHIFT_C_DC	51.3 %	68.7 %

Are all of the PID values within the limits?

Yes

GO to A11

No	INSTALL a new gear shift position sensor and magnet as a matched pair. REFER to: Gear Shift Position Sensor

A11 CHECK THE GEAR SHIFT POSITION SENSOR FOR CORRECT OPERATION IN FOURTH GEAR

Start engine and allow to idle.

Engage parking brake.

Press and hold the clutch pedal for the duration of this test.

Position the gear shift lever in fourth gear. Remove hand from gear shift lever.

Access the PCM and monitor the gear shift position sensor data.

PID	Lower Limit	Upper Limit
TR_NEUTRAL_RAW	13.1 %	26.9 %
TR_NTRL_RAW2	11.7 %	23.3 %
GEAR_SHIFT_C_DC	51.3 %	68.7 %

Are all of the PID values within the limits?

Yes

GO to A12

No	INSTALL a new gear shift position sensor and magnet as a matched pair. REFER to: Gear Shift Position Sensor

A12 CHECK THE GEAR SHIFT POSITION SENSOR FOR CORRECT OPERATION IN FIFTH GEAR

Start engine and allow to idle.

Engage parking brake.

Press and hold the clutch pedal for the duration of this test.

Position the gear shift lever in fifth gear. Remove hand from gear shift lever.

Access the PCM and monitor the gear shift position sensor data.

PID	Lower Limit	Upper Limit
TR_NEUTRAL_RAW	73.1 %	86.9 %
TR_NTRL_RAW2	56.7 %	68.3 %
GEAR_SHIFT_C_DC	71.3 %	88.7 %

Are all of the PID values within the limits?

Yes

GO to A13

No	INSTALL a new gear shift position sensor and magnet as a matched pair. REFER to: Gear Shift Position Sensor

A13 CHECK THE GEAR SHIFT POSITION SENSOR FOR CORRECT OPERATION IN SIXTH GEAR

Start engine and allow to idle.

Engage parking brake.

Press and hold the clutch pedal for the duration of this test.

Position the gear shift lever in sixth gear. Remove hand from gear shift lever.

Access the PCM and monitor the gear shift position sensor data.

PID	Lower Limit	Upper Limit
TR_NEUTRAL_RAW	13.1 %	26.9 %
TR_NTRL_RAW2	11.7 %	23.3 %
GEAR_SHIFT_C_DC	71.3 %	88.7 %

Are all of the PID values within the limits?

Yes

GO to A14

No	INSTALL a new gear shift position sensor and magnet as a matched pair. REFER to: Gear Shift Position Sensor

A14 CHECK THE GEAR SHIFT POSITION SENSOR FOR CORRECT OPERATION IN REVERSE

Start engine and allow to idle.

Engage parking brake.

Press and hold the clutch pedal for the duration of this test.

Position the gear shift lever in reverse gear. Remove hand from gear shift lever.

Access the PCM and monitor the gear shift position sensor data.

PID	Lower Limit	Upper Limit
TR_NEUTRAL_RAW	73.1 %	86.9 %
TR_NTRL_RAW2	56.7 %	68.3 %
GEAR_SHIFT_C_DC	11.3 %	28.7 %

Are all of the PID values within the limits?

Yes

GO to A15

No	INSTALL a new gear shift position sensor and magnet as a matched pair. REFER to: Gear Shift Position Sensor

A15 CHECK FOR CORRECT PCM (POWERTRAIN CONTROL MODULE) OPERATION

Ignition OFF.

Disconnect and inspect the PCM connectors.

Repair:
- corrosion (install new connector or terminals - clean module pins)
- damaged or bent pins - install new terminals/pins
- pushed-out pins - install new pins as necessary

Reconnect the PCM connectors. Make sure they seat and latch correctly.

Operate the system and determine if the concern is still present.

Is the concern still present?

Yes

CHECK for an applicable TSB, GSB, SSM, or FSA. If a service bulletin exists for this concern, discontinue this test and follow bulletin instructions. If none address this concern, INSTALL a new PCM. Refer to the appropriate Removal and Installation procedure in the appropriate Electronic Engine Controls service information .

No	The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.