Pinpoint Test A: Gear Shift Position Sensor Circuit Faults

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

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

Refer to ELECTRONIC ENGINE CONTROLS - 2.3L 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 TRS_NEU_VAL_RAW and TR_NEU2_RAW 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, REVERSE, or UNDEFINED for crawler gear. 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. The sensor data is used for several vehicle features and functions including rev matching, reverse camera activation, reverse parking aid, hill start assist, and reverse lamps.

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 TRS_NEU_VAL_RAW on pin 2, GEAR_SHIFT_C_DC on pin 3, and TR_NEU2_RAW 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 gear shift 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_NPS_FREQ_A is less than 225 Hz or greater than 275 Hz when measured by the PCM at C175B-95
PCM P086C:00	Neutral Position Sensor "A" Circuit Low: No Sub Type Information	This DTC sets when the raw gear shift 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. TRS_NEU_VAL_RAW is less than 7% when measured by the PCM at C175B-95
PCM P086D:00	Neutral Position Sensor "A" Circuit High: No Sub Type Information	This DTC sets when the raw gear shift 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. TRS_NEU_VAL_RAW is greater than 93% when measured by the PCM at C175B-95
PCM P08AE:00	Neutral Position Sensor "B" Circuit Range/Performance: No Sub Type Information	This DTC sets when the raw gear shift 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_NPS_FREQ_B is less than 225 Hz or greater than 275 Hz when measured by the PCM at C175B-99
PCM P08AF:00	Neutral Position Sensor "B" Circuit Low: No Sub Type Information	This DTC sets when the raw gear shift 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_NEU2_RAW is less than 7% when measured by the PCM at C175B-99
PCM P08B0:00	Neutral Position Sensor "B" Circuit High: No Sub Type Information	This DTC sets when the raw gear shift 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_NEU2_RAW is greater than 93% when measured by the PCM at C175B-99
PCM P095A:00	Gear Shift Position Circuit "C": No Sub Type Information	This DTC sets when the raw gear shift 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 C175B-58
PCM P095C:00	Gear Shift Position Circuit "C" Low: No Sub Type Information	This DTC sets when the raw gear shift 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 C175B-58
PCM P095D:00	Gear Shift Position Circuit "C" High: No Sub Type Information	This DTC sets when the raw gear shift 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 C175B-58

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 C175B.

Disconnect gear shift position sensor C1854.

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	C175B-118
Gear shift position sensor "A" C1854-2	Courtesy of FORD MOTOR COMPANY	C175B-95
Gear shift position sensor "C" C1854-3	Courtesy of FORD MOTOR COMPANY	C175B-58
Gear shift position sensor "B" C1854-4	Courtesy of FORD MOTOR COMPANY	C175B-99
SIGNAL RETURN C1854-6	Courtesy of FORD MOTOR COMPANY	C175B-73

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 C175B.

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 A16

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 A16

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

Ignition OFF.

Connect gear shift position sensor C1854.

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
TRS_NEU_VAL_RAW	45.77 %	54.23 %
TR_NEU2_RAW	36.85 %	43.15 %
GEAR_SHIFT_C_DC	55.01 %	64.99 %
TR_NPS_FRQ_A	225 Hz	275 Hz
TR_NPS_FRQ_B
GEAR_SHIFT_C_FRQ

Are all of the PID values within the limits?

Yes

GO to A8

No	Install a new shift shaft and gear shift position sensor 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
TRS_NEU_VAL_RAW	73.97 %	86.03 %
TR_NEU2_RAW	58.00 %	67.00 %
GEAR_SHIFT_C_DC	35.01 %	44.99 %

Are all of the PID values within the limits?

Yes

GO to A9

No	Install a new shift shaft and gear shift position sensor 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
TRS_NEU_VAL_RAW	13.97 %	26.03 %
TR_NEU2_RAW	13.00 %	22.00 %
GEAR_SHIFT_C_DC	35.01 %	44.99 %

Are all of the PID values within the limits?

Yes

GO to A10

No	Install a new shift shaft and gear shift position sensor 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
TRS_NEU_VAL_RAW	73.97 %	86.03 %
TR_NEU2_RAW	58.00 %	67.00 %
GEAR_SHIFT_C_DC	55.01 %	64.99 %

Are all of the PID values within the limits?

Yes

GO to A11

No	Install a new shift shaft and gear shift position sensor 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
TRS_NEU_VAL_RAW	13.97 %	26.03 %
TR_NEU2_RAW	13.00 %	22.00 %
GEAR_SHIFT_C_DC	55.01 %	64.99 %

Are all of the PID values within the limits?

Yes

GO to A12

No	Install a new shift shaft and gear shift position sensor 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
TRS_NEU_VAL_RAW	73.97 %	86.03 %
TR_NEU2_RAW	58.00 %	67.00 %
GEAR_SHIFT_C_DC	75.01 %	84.99 %

Are all of the PID values within the limits?

Yes

GO to A13

No	Install a new shift shaft and gear shift position sensor 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
TRS_NEU_VAL_RAW	13.97 %	26.03 %
TR_NEU2_RAW	13.00 %	22.00 %
GEAR_SHIFT_C_DC	75.01 %	84.99 %

Are all of the PID values within the limits?

Yes

GO to A14

No	Install a new shift shaft and gear shift position sensor 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
TRS_NEU_VAL_RAW	73.97 %	86.03 %
TR_NEU2_RAW	58.00 %	67.00 %
GEAR_SHIFT_C_DC	15.01 %	24.99 %

Are all of the PID values within the limits?

Yes

GO to A15

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

A15 CHECK THE GEAR SHIFT POSITION SENSOR FOR CORRECT OPERATION IN CRAWLER

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 crawler gear. Remove hand from gear shift lever.

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

PID	Lower Limit	Upper Limit
TRS_NEU_VAL_RAW	13.97 %	26.03 %
TR_NEU2_RAW	13.00 %	22.00 %
GEAR_SHIFT_C_DC	15.01 %	24.99 %

Are all of the PID values within the limits?

Yes

GO to A16

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

A16 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, Refer to PCM GUIDED ROUTINE TESTING

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.