TM 5-3805-296-23-2
0091
Table 1. 1840 Tractor Parking Brake Pressure Switch Diagnostic Codes Continued.
091
CID FMI
TEST OR INSPECTION
CORRECTIVE ACTION
Test Step 8. Test Main Cab Wiring
1840-03 Tractor Parking
Harness for High Resistance or
Brake Pressure Switch
Open.
Voltage Above Normal
1. Remove jumper wire from
Continued
terminal 17 and terminal 18 of
connector J-C3 (WP 0012,
Figure 101).
2. Disconnect connector W-C12
(WP 0012, Figure 88) from
transmission/chassis ECM.
3. Connect jumper wire between
terminal 20 and terminal 45 of
connector W-C12
(WP 0012, Figure 89).
4. Using digital multimeter
Resistance 5.0 Ohms or Less
(WP 0540), measure resistance
Proceed to step 5.
between connector W-C1
Resistance Greater Than 5.0 Ohms
terminal 5 and terminal 13
Replace main cab wiring harness
(WP 0012, Figure 99).
(WP 0505).
Proceed to Test Step 9.
5. Using digital multimeter
Resistance 5.0 Ohms or Less
(WP 0540), measure resistance
Replace transmission/chassis ECM
between connector W-C12
(WP 0495).
terminal 9 and terminal 45
Proceed to Test Step 9.
(WP 0012, Figure 89).
Resistance Greater Than 5.0 Ohms
Replace main cab wiring harness
(WP 0505).
Proceed to Test Step 9.
Test Step 9. Verify Malfunction is
Resolved.
1. Ensure all harness connectors are
connected.
2. Turn battery disconnect switch and
ignition switch to ON position
(TM 5-3805-296-10).
3. At MSD, check for active
1840-3 Tractor Parking Brake
diagnostic codes (WP 0008).
Pressure Switch Voltage Above
Normal Becomes Inactive
Troubleshooting complete.
1840-3 Tractor Parking Brake
Pressure Switch Voltage Above
Normal Remains Active Repeat
troubleshooting from the beginning.
0091-6
