Ford F150 Pickup. Instruction - part 1936

SYMPTOM CHART - ELECTRONIC SHIFT ON THE FLY (ESOF) 

Symptom Chart 

SYMPTOM CHART 

P1838

Transmission Transfer Case Shift Motor 

Circuit Failure

GEM

REFER to SYMPTOM CHART .

P1846 Transmission Transfer Case Contact Plate 

'A' Circuit Failure

GEM

REFER to SYMPTOM CHART .

P1850 Transmission Transfer Case Contact Plate 

'B' Circuit Failure

GEM

REFER to SYMPTOM CHART .

P1854 Transmission Transfer Case Contact Plate 

'C' Circuit Failure

GEM

REFER to SYMPTOM CHART .

P1858 Transmission Transfer Case Contact Plate 

'D' Circuit Failure

GEM

REFER to SYMPTOM CHART .

P1866

Transmission Transfer Case System 

Concern - Servicing Required

GEM

REFER to SYMPTOM CHART .

P1867 Transmission Transfer Case Contact Plate 

General Circuit Failure

GEM

REFER to SYMPTOM CHART .

P1876

Transmission Transfer Case 2-Wheel 

Drive Solenoid Circuit Failure

GEM

GO to PINPOINT TEST C .

P1877

Transmission Transfer Case 2-Wheel 

Drive Solenoid Circuit Short to Battery

GEM

GO to PINPOINT TEST C .

P1891 Transmission Transfer Case Contact Plate 

Ground Return Open Circuit

GEM

REFER to SYMPTOM CHART

Condition

Possible Sources

Action

The vehicle does not shift between 2WD and 4WD 
modes correctly

z

4 WD mode switch.  

z

Transfer case shift 
relays.  

z

Contact plate A, B, C, 
or D.  

z

Transfer case shift 
motor.  

z

Circuitry.  

z

Transfer case 
mechanism.  

GO to PINPOINT 

TEST A .

The vehicle does not shift between 4H and 4L modes 
correctly

z

4WD mode switch.  

z

Neutral safety switch.  

z

Brake pedal position 
(BPP) switch.  

z

Transfer case 

GO to PINPOINT 

TEST B .

 

2003 Ford Pickup F150 

2003 TRANSMISSIONS Transfer Case - General Information - F150 Pickup

  

PINPOINT TESTS 

Pinpoint Test A: Vehicle Does Not Shift Between 2WD & 4WD Modes Correctly 

mechanism.  

z

Digital transmission 
range (TR) sensor.  

z

Circuitry.  

The front axle is not engaging correctly (transfer case 
motor movement OK)

z

4x4 solenoid.  

z

4x2 solenoid.  

z

Vacuum motor.  

z

Circuitry.  

z

Vacuum lines.  

z

Front differential 
mechanism.  

GO to PINPOINT 

TEST C .

The 4x4 indicator does not operate correctly

z

Bulb.  

z

Digital (TR)sensor.  

z

Circuitry.  

GO to PINPOINT 

TEST D .

The 4x4 HIGH does not engage at speed correctly 
(driveline does not synchronize correctly) but does 
engage at rest

z

ESOF clutch relay.  

z

Transfer case electric 
clutch.  

z

Transfer case clutch 
armature.  

z

Hub release spring.  

z

Circuitry.  

GO to PINPOINT 

TEST E .

No communication with the module - GEM

z

Fuse(s).  

z

Circuitry.  

z

GEM.  

z

CJB.  

GO to PINPOINT 

TEST F .

 

2003 Ford Pickup F150 

2003 TRANSMISSIONS Transfer Case - General Information - F150 Pickup

  

Fig. 12: Pinpoint Test A: Vehicle Does Not Shift Between 2WD & 4WD Modes Correctly (Steps A1-A4) 
Courtesy of FORD MOTOR CO. 

 

2003 Ford Pickup F150 

2003 TRANSMISSIONS Transfer Case - General Information - F150 Pickup

  

Fig. 13: Pinpoint Test A: Vehicle Does Not Shift Between 2WD & 4WD Modes Correctly (Steps A5-A8) 
Courtesy of FORD MOTOR CO. 

 

2003 Ford Pickup F150 

2003 TRANSMISSIONS Transfer Case - General Information - F150 Pickup