TM 5-3805-296-23-2
0073
Table 1. 1278 Apron Lower Proportional Solenoid Diagnostic Codes Continued.
073
CID FMI
TEST OR INSPECTION
CORRECTIVE ACTION
Test Step 4. Test for Shorted Main
1278-03 Apron Lower
Cab Wiring Harness.
Solenoid Voltage Above
1. Disconnect connector W-C13
Normal Continued
(WP 0012, Figure 89) from
transmission/chassis ECM.
2. Disconnect connector W-C12
(WP 0012, Figure 88) from
transmission/chassis ECM.
3. Using digital multimeter
Continuity Replace main cab wiring
(WP 0540), test for continuity
harness (WP 0505).
between connector W-C3 terminal
Proceed to Test Step 5.
10 (WP 0012, Figure 139) and all
No Continuity Proceed to step 4.
other terminals in connector W-C3
(WP 0012, Figure 139).
4. Using digital multimeter
Continuity Replace main cab wiring
(WP 0540), test for continuity
harness (WP 0505).
between connector W-C13
Proceed to Test Step 5.
terminal 3 (WP 0012, Figure 89)
No Continuity Proceed to step 5.
and all other terminals
in connector W-C13
(WP 0012, Figure 89).
5. Using digital multimeter
Continuity Replace main cab wiring
(WP 0540), test for continuity
harness (WP 0505).
between connector W-C13
Proceed to Test Step 5.
terminal 3 (WP 0012, Figure 89)
No Continuity Replace transmission/
and all terminals in connector
chassis ECM (WP 0495).
W-C12 (WP 0012, Figure 88).
Proceed to Test Step 5.
Test Step 5. 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
1278-3 Apron Lower Solenoid
diagnostic codes (WP 0008).
Voltage Above Normal Becomes
Inactive Proceed to step 4.
1278-3 Apron Lower Solenoid
Voltage Above Normal Remains
Active Repeat troubleshooting from
the beginning.
4. Turn ignition switch and battery
disconnect switch to OFF position
(TM 5-3805-296-10).
0073-6
