Lull 944E-42 Service Manual - Manual (Page 672)

Electrical System
9.162 Model 644E-42/944E-42 Rev. 6/04
9.10.14 Engine Air-Intake Heater Indicator Troubleshooting (644E-42 Option, 944E-42 Standard)
Grid heater
OK.
Yes No
0000000
RPM X 100
5
10
15
30
20
25
F
1/2
E 104
176
80
248
120 °C
°F
r/min
D
MU4390
Check for voltage at grid
heater element
Engine air-intake
heater indicator
stays ON
while operating.
Replace harness
If temperature is below
50° F (10° C), grid heater
post heat can be on up to
two (2) minutes.
Check for voltage at grid
heater relay coils.
If OK
Replace grid heater relays.
Does grid heater cycle ON/OFF?
If OK
Not
OK
Not
OK
If temperature is above
50° F (10° C):
Engine Air-Intake
Heater Indicator
Activate the ECM diagnostic system
and read the code as indicated by the
flashing lights on the indicator, located
on the left side of the dash between
the park brake switch and the
transmission disconnect switch.
Contact your local Cummins dealer
for an explanation of the code, refer to
the Cummins Engine Owners Manual
or call the Cummins Customer
Assistance Center at
1-800-343-7357.
944E-42 644E-42
Replace grid heater
control box.
Before troubleshooting any
electrical circuit, ALWAYS begin
by checking the following:
1. Fuses.
2. Battery for proper charge.
3. All connections relating to
circuit are clean and tight.
4. All grounding straps are intact
and securely fastened, refer to
Section 9.1.12, “General
Overview (Vehicle Ground
Strap Locations).”
5. Check dash panel bulbs for
proper function.