Electrical system – Lull 944E-42 Service Manual User Manual
Page 649
9.139
Model 644E-42/944E-42
Rev. 6/04
Electrical System
Not
OK
Check for battery voltage
at pin 2, wire [WL4B]
(RED/WHT) and pin 5,
wire [WL4C] (RED/WHT)
at worklight switch.
Not
OK
If OK
Not
OK
If OK
Replace cab
roadlight harness.
Replace worklight switch.
Not
OK
Check for battery voltage at
pin A, wire [WL5A] (LT BLU)
and pin B, wire [WL6] (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 [WLG9]
(BLK) & [WL6B] (YEL) (Left),
[WLG10] (BLK) & [WL6C]
(YEL) (Right) on rear
worklights, pins A & B, wire
[WL5C] (LT BLU) &
[WLG5] (BLK) boom
worklight connector and pins
N & P, wire [WLG6] (BLK) &
[WL5D] (LT BLU) (Left),
[WLG7] (BLK) & [WL5E]
(LT BLU) (Right) on front
worklights.
Check for battery voltage at
pin 3, wire [WL5] (LT BLU),
and pin 6, wire [WL6] (YEL) at
worklight switch.
Worklights remain OFF
with ignition switch in the
RUN position and the
bottom of the worklight
switch pushed in.
Replace vehicle
roadlight harness.
Check for proper ground at
wire [EG8] (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. Follow the steps listed at,
Section 9.8.41, “Light Power
Relay Circuit &
Troubleshooting (Option),”
before troubleshooting the
worklights circuit.
5. If one of the worklights work,
the circuit is fine, the failed
bulb needs to be replaced.