SFN-20231108B-Install the dolly master electrical kit_option 2

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TICO Document #: SFN-20231108B (formerly TES-240)

Complication: The previous design for the dolly master supplies constant air pressure to the cylinder while it is in the raised/locked position. The constant air pressure could potentially leak through the seals of the cylinder causing a loss of pressure in the air system.

Description of Procedure: Install the dolly master electrical upgrade kit

Units Affected: 5639-5968; 6323-6382; 6981-7020; 7075-7140; 7193-7314

Parts Required: KIT - DOLLY MASTER OPTION 2, ELECTRICAL UPGRADE 970044 (QTY 1)

Planned Labor: 90 minutes


Instructions:

  1. Park the vehicle on a flat surface, apply the parking brake, and chock wheels. If your company utilizes a “Lock Out, Tag Out” policy, you should employ it during this procedure.


  1. Remove (6) #10-32 x 1/2” button head socket cap screws to free the LH dash switch panel. Retain all hardware, see Figures 3a and 3b.


  1. Disconnect the dolly master/magnet harness from the rocker switches shown in Figures 4a and 4b.

    Note: The dolly master/magnet harness P/N is 620870 unless the truck serial number is between (5101-5260) then the harness P/N is 621005.


  1. Remove the old dolly master rocker switch located on the bottom row of the LH dash panel.

  2. Install the new rocker switch P/N: 910801, see Figure 5a.

    Note: The old dolly master rocker switch that is already installed on trucks that use Kit P/N: 970044 will have identical graphics but will differ in the pin terminal configuration. The new switch will a blade terminal installed at pin 1 on the back of the switch, see Figure 5b.


  1. Remove (14) 1/4” button head socket cap screws from the driver’s side front panel of the cab. Retain all hardware, see Figures 6a and 6b.


  1. Disconnect the three connectors labeled “Options”, “Power” and “Proximity Sensor” on the dolly master/magnet harness. The connectors will be in the upper right-hand corner when looking up at the dash. See Figures 7a and 7b.


  1. Remove the old dolly master/magnet harness and discard it.

  2. Install the new dolly master harness P/N: 621230.

  3. Route the rocker switch connector side of the harness through the lower left opening in the dash frame. See Figures 8a and 8b.

    Note: Be sure to route the harness in the specified location shown in Figure 8b.


  1. Connect both switch connectors (S1) Magnet and (S2) Dolly Master to their corresponding rocker switch, see Figures 9a and 9b.


  1. Re-install the LH dash switch panel using (6) #10-32 x 1/2” button head socket cap screws. Torque screws to 51 in-lb. See Figure 10a.


  1. Remove the dolly master raise relay from the relay mounting bracket on harness P/N: 621230, and retain the relay.

  2. Remove the (1) #10-32 x 1/2” button head socket cap screw shown in Figures 11a and 11b, and retain all hardware.


  1. Secure the relay mounting bracket to the dash using the hardware you retained in the previous step. Tighten to 51 in-lb. See Figures 12a and 12b.


  1. Re-install the dolly master raise onto the mounting bracket. See Figures 13a and 13b.


  1. Connect the “Options” and “Power” connectors on harness P/N: 621230 to the dash harness connectors labeled “Options” and “Options Power”, respectively. See Figures 14a and 14b.


  1. Connect the remaining connector labeled “Proximity Sensor” on harness P/N: 621230 to the dolly master proximity sensor harness P/N: 621011, see Figure 15a.

  2. Complete a thorough inspection of the installation to confirm no loose connections and no slack remain on the harness; see Figure 15b.


  1. Locate and disconnect the “Spare 3 Options” connector that is located directly underneath the cab PDC. Remove cable ties as necessary to free the connector. See Figures 16a and 16b.

    *This connects to the exterior dolly master harness P/N: 621032 connectors labeled “Options”. See Figure 16b.


  1. Lift the cab to the fully raised position and secure in place.

  2. Locate the mounting bracket for the dolly master/magnet air solenoids and disconnect the connectors labeled “Magnet”, “DM1” and “DM2”. Remove cable ties as necessary to free the connectors. See Figures 17a and 17b.

  3. Remove harness P/N: 621032 and discard.


  1. Lower the air solenoid bracket by removing the (8) #10-32 x 2-1/2” Phillips pan head machine screws shown in Figures 18a and 18b.


  1. Locate the “dolly master raise solenoid” using Table 2 and Figures 19a, and 19b to identify the correct air solenoid.


  1. Disconnect the (2) 1/4” air hoses from ports 1 and 3 and re-install them in the reverse configuration.

  2. Port 1 should now be the air supply, and port three the air exhaust, see Figures 20a and 20b.


  1. Re-install the air solenoid bracket using the hardware that was retained earlier and torque to 51 in-lb. See Figures 21a and 21b.


  1. Install the new exterior dolly master/magnet harness P/N: 620871 that’s included in KIT P/N: 970044, see Figure 22a.

  2. See Table 2 on page 21 to identify the correct air solenoids when completing the next step.

  3. Connect the (3) connectors labeled “DM1 Raise”, “DM2 Lower,” and “Magnet” to the respective air solenoid, see Figure 22b.


  1. Connect the “Spare 3 Options” connector to the harness P/N: 620871 connectors labeled “Options”, see Figures 23a and 23b.

  2. Confirm that connectors are fully seated and install new cable ties as needed.


  1. Route the new exterior dolly/master harness P/N: 620871 and install cable ties along harness routing as needed, see Figure 24a.

  2. Move any slack from the harness over to the air solenoid connectors and bundle harness together with cable ties as needed. See Figure 24b.

  3. Complete a thorough inspection of the installation to confirm no loose connections and no slack remain on the harness.


  1. Re-install (14) 1/4” button head socket cap screws from the driver’s side front panel of the cab. Torque to 108 in-lb. See Figures 25a and 25b.


  1. Perform a dolly master operational checkout.

    a. Start truck and allow 5 minutes for air pressure to build up and stabilize.

    b. Press and hold the dolly master rocker switch:

    • The spring-loaded locking latch should release and lower the dolly master to the ground. The dolly master should remain lowered until the switch is released.

    • When the locking latch is unlocked the proximity sensor sends a signal to the rocker switch and will illuminate the indicator light.

    c. Release the dolly master rocker switch:

    • Air will be supplied to the cylinder, raising the dolly master.

    • Air pressure will remain on the cylinder until the spring-loaded latch has been engaged.

    • When the latch is locked the indictor light turns off.

    • Air pressure should then be exhausted from the dolly master cylinder.


  1. Remove “Lock Out, Tag Out” plaque.


  1. Return vehicle to service.