Chrysler RAM50/D50/Arrow 1979-1993 Repair Guide

Park/Neutral Position Switch

Print

The inhibitor switch on the trucks also houses the back up light switch.

REMOVAL & INSTALLATION



1979-86 Models
  1. Disconnect the negative battery cable from the battery.
  2.  
  3. While pushing the button, remove the selector handle assembly from the selector lever by loosening the set screw.
  4.  
  5. Remove the console box, then remove the position indicator assembly upward by loosening the attaching screws.
  6.  
  7. Disconnect the inhibitor (park/neutral switch) switch wiring.
  8.  
  9. Loosen and remove the attaching screws of the inhibitor switch. Remove the switch from the selector assembly.
  10.  

To install:
  1. Loosely secure the inhibitor switch to the selector assembly.
  2.  
  3. Connect the inhibitor switch wiring.
  4.  
  5. Adjust the inhibitor switch-refer to the following procedures for adjustment.
  6.  
  7. Set the position indicator back in place, then secure it in place with the mounting screws.
  8.  
  9. Install the console box.
  10.  
  11. Mount the selector handle to the lever and secure in place by tightening the set screw.
  12.  

1987-89 Models

  1. Disconnect the negative battery cable from the battery.
  2.  
  3. Remove the floor console, the selector handle and the indicator panel-refer to the shift linkage removal procedures in this section.
  4.  
  5. Unplug the inhibitor switch (park/neutral switch) harness connector.
  6.  
  7. Unscrew the retaining screws and remove the inhibitor switch from the bracket.
  8.  

To install:
  1. Loosely attach the inhibitor switch to the bracket.
  2.  
  3. Adjust the switch-refer to the adjustment procedures.
  4.  
  5. Reassemble the shifter assembly.
  6.  
  7. Connect the negative battery cable to the battery.
  8.  

1990-93 Models See Figure 1

  1. To test the switch, remove the wiring connector from the switch and test for continuity between the center pin of the switch and the transmission case. Continuity should only exist when the transmission is in Park or Neutral.
  2.  
  3. Check the gearshift linkage adjustment before replacing a switch which tests bad.
  4.  



Click image to see an enlarged view

Fig. Fig. 1: Unscrew the park/neutral switch from the transmission case and drain the fluid into a container-R4AC1 transmissions

  1. Unscrew the switch from the transmission case and allow the fluid to drain into a container. Move the selector lever to the Park and then to Neutral positions, and inspect to see that the switch operating lever fingers are centered in the switch opening in the case.
  2.  

To install:
  1. Screw the switch and new seal into the transmission case and tighten to 25 ft. lbs. (34 Nm). Retest the switch with the test lamp or ohmmeter.
  2.  
  3. Add automatic transmission fluid to the transmission to bring it up to the proper level.
  4.  
  5. The back up lamp switch circuit is through the two outside terminals of the 3 terminal switch.
  6.  
  7. To test the back up switch, remove the wiring from the switch and test for continuity between the two outside pins.
  8.  
  9. Continuity should exist only with the transmission in reverse.
  10.  
  11. No continuity should exist from either pin to the case.
  12.  

ADJUSTMENT




WARNING
If the switch is faulty, the engine may start with the vehicle "in gear". If this happens the vehicle will accelerate when the engine starts. Keep the brakes on and be ready to switch the key off instantly.1979-86 Models See Figures 2 and 3

  1. Place the selector lever so that it is in the N position, then temporarily fasten the inhibitor switch (park/neutral switch) to the selector lever bracket. By using an ohmmeter, measure the continuity between the switch terminals BY and BY; move the switch forward and backward, and set it to the position of first continuity (where it first shows continuity).
  2.  



Click image to see an enlarged view

Fig. Fig. 2: Set the selector lever in the position shown, then adjust the switch so that it shows continuity-MA 904A transmissions



Click image to see an enlarged view

Fig. Fig. 3: Slide the switch sideways until the proper clearance of 1.5mm (0.06 in.) exists-MA 904A transmissions

  1. Slide the inhibitor switch (park/neutral switch) so that there is 0.06 in. (1.5mm) clearance between the switch and the shifter lever.
  2.  
  3. Tighten the two attaching screws until snug.
  4.  

1987-89 4WD Models See Figures 4, 5 and 6

  1. Make sure the harness connector is securely attached.
  2.  
  3. Loosen the mounting screws.
  4.  
  5. Set the shift lever so that the pin at the end of the rod is at the neutral position-see the illustration.
  6.  
  7. Using a circuit tester between terminals 2-BY and 2-BY of the inhibitor switch connector, check the continuity when the inhibitor switch is moved back and forth, and mark the bracket.
  8.  
  9. Tighten the inhibitor switch mounting screws so that the switch edge is 0.1 in. (2.5mm) from the close edge of the lever.
  10.  



Click image to see an enlarged view

Fig. Fig. 4: To adjust the park/neutral switch, move the selector lever until the selector rod is in the position shown-KM 148 transmissions



Click image to see an enlarged view

Fig. Fig. 5: Once the selector lever is in the correct position, use an ohmmeter to set the park/neutral switch-KM 148 transmissions



Click image to see an enlarged view

Fig. Fig. 6: Move the park/neutral switch to the side until the correct clearance has been reached-KM 148 transmissions

 
label.common.footer.alt.autozoneLogo