TM 5-2420-231-23-1
0028
Table 1. Engine Grid Heater Indicator Fault - Continued.
028
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
2. Disconnect side console wiring
Engine Grid Heater Indicator
harness connector (WP 0007,
Fault - Continued
Figure 24) from main chassis
wiring harness connector (WP
0007, Figure 25) (WP 0170).
3. Using a digital multimeter, test for
Continuity - Proceed to Test Step 5.
continuity between main chassis
No Continuity - Replace side console
wiring harness connector (WP
wiring harness (WP 0170).
0007, Figure 25) terminal 7B and
Connect grid heater wiring harness
machine ground. There should be
connector (WP 0007, Figure 11) to grid
no continuity.
heater controller (WP 0007, Figure 12).
Install air cleaner barrier curtain (WP
0099).
Proceed to Test Step 10.
Test Step 5. Check for Shorted Grid
Heater Wiring Harness.
1. Disconnect grid heater wiring har-
ness connector (WP 0007, Figure
15) from main chassis wiring har-
ness connector (WP 0007, Figure
16) (WP 0161).
2. Using a digital multimeter, test for
Continuity - Replace grid heater wiring
continuity between grid heater wir-
harness (WP 0161).
ing harness connector (WP 0007,
Proceed to Test Step 10.
Figure 15) terminals 1 and 4.
No Continuity - Replace main chassis
There should be no continuity.
wiring harness (WP 0154).
Proceed to Test Step 10.
Test Step 6. Check for Open Grid
Heater Wiring Harness.
1. Install a jumper wire between side
console wiring harness connector
(WP 0007, Figure 28) pins 16 and
36.
2. Using a digital multimeter, mea-
Resistance 5.0 Ohms or Less -
sure resistance on grid heater wir-
Replace grid heater controller (WP
ing harness (WP 0007, Figure 11)
0160).
terminals 1 and 8. Resistance
Remove jumper wire from side console
should be 5.0 ohms or less.
wiring harness (WP 0007, Figure 28)
pins 16 and 36.
Proceed to Test Step 10.
Resistance Greater Than 5.0 Ohms -
Proceed to Test Step 7.
0028-6
