Electrical system – Lull 944E-42 Service Manual User Manual
Page 647

9.137
Model 644E-42/944E-42
Rev. 6/04
Electrical System
Not
OK
Check for battery voltage at pin
2, wire [WL1A] (RED/WHT)
and 5, wire [WL1C] (RED/
WHT) at worklight switch.
Not
OK
If OK
Not
OK
If OK
Replace cab
roadlight harness.
Replace vehicle
roadlight harness.
Replace worklight switch.
Not
OK
Check for battery voltage at
pin A, wire [WL2] (LT BLU) and
pin B, wire [WL3] (YEL) on
worklight female connector.
If OK
Replace cab
roadlight harness.
If OK
Replace failed bulb.
Check for battery voltage at
pins N & P, wire [WLG2] (BLK)
& [WL3B] (YEL) (Left),
[WLG3] (BLK) & [WL3C] (YEL)
(Right) on rear worklights and
pins A & B, wire
[WL2A] (ORG) &
[WLG1] (BLK) boom
worklight connector.
Check for battery voltage at
pin 3, wire [WL2] (LT BLU),
and pin 6, wire [WL3] (YEL) at
worklight switch.
Worklights remain OFF
with ignition switch in the
RUN position and the
bottom of the worklight
switch pushed in.
Check for proper ground at
wire [EG7] (BLK) at ground
buss bar.
If OK
Clean, tighten and recheck.
Not
OK
Before troubleshooting any 
electrical circuit, ALWAYS begin 
by checking the following:
1. Fuses.
2. All connections relating to
circuit are clean and tight.
3. All grounding straps are intact
and securely fastened, refer to 
Section 9.1.12, “General 
Overview (Vehicle Ground 
Strap Locations).”
4. Verify that the high or low
beam circuits are operating. If 
not, follow the steps listed at, 
Section 9.8.41, “Light Power 
Relay Circuit & 
Troubleshooting (Option),” 
before troubleshooting the 
roadlight worklights circuit.
5. If one of the worklights work,
the circuit is fine, the failed 
bulb needs to be replaced.
