TM 5-2420-231-23-1
0019
Table 1. Tachometer Does Not Function or Is Inaccurate - Continued.
019
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
5. Using a digital multimeter, mea-
Tachometer Does Not
Resistance 5.0 Ohms or Less -
sure resistance between side con-
Proceed to step 6.
Function or Is Inaccurate -
sole wiring harness connector (WP
Continued
Resistance Greater Than 5.0 Ohms -
0007, Figure 24) terminal 4C and
Replace side console wiring harness
side console wiring harness con-
(WP 0170).
nector (WP 0007, Figure 28) termi-
Proceed to Test Step 6.
nal 19. Resistance should be 5.0
ohms or less.
6. Using a digital multimeter, test for
Continuity - Replace side console
continuity between side console
wiring harness (WP 0170).
wiring harness connector (WP
Proceed to Test Step 6.
0007, Figure 24) 4C and machine
No Continuity - Proceed to step 7.
ground. There should be no conti-
nuity.
7. Install a jumper wire between "W"
terminal connector (WP 0007, Fig-
ure 30) and machine ground.
8. Using a digital multimeter, mea-
Resistance 5.0 Ohms or Less -
sure resistance between rear main
Proceed to step 9.
chassis wiring harness connector
Resistance Greater Than 5.0 Ohms -
(WP 0007, Figure 24) terminal 4C
Replace side console wiring harness
and machine ground. Resistance
(WP 0170).
should be 5.0 ohms or less.
Proceed to Test Step 6.
9. Remove jumper wire from "W" ter-
minal connector (WP 0007, Figure
30) and machine ground.
10. Using a digital multimeter, test for
No Continuity - Replace instrument
continuity between "W" terminal
cluster (WP 0177).
connector (WP 0007, Figure 30)
Proceed to Test Step 6.
and machine ground. There should
Continuity - Replace main chassis
be no continuity.
wiring harness (WP 0154).
Proceed to Test Step 6.
0019-10