TM 5-3825-270-23&P
0059
DECISION
No - Place tachometer pulse adjustment dial to pulse 5. Verify problem is solved. (Step 8 - Does cab control box
tachometer operate normally?)
Yes - Go to step 4. (Step 4 - Are 22 to 28 VDC measured at white wire on cab control box tachometer?)
STEP 4
Are 22 to 28 VDC measured at white wire on cab control box tachometer?
1.
Rotate EMERGENCY STOP switch to on position. (TM 5-3825-270-10)
2.
Ensure multimeter is set to measure voltage.
WARNING
Remove all jewelry such as rings, ID tags, bracelets, etc., prior to working on or around
vehicle. Jewelry and tools can catch on equipment, contact positive electrical circuits, and
cause a direct short, severe burns, or electrical shock. Failure to comply may result in injury
or death to personnel.
3.
Connect red multimeter lead to white wire on cab control box tachometer.
CAB
CONTROL BOX
TACHOMETER
BACK OF CAB
CONTROL BOX
WHITE WIRE(S)
BLACK WIRE(S)
Figure 6. Cab Control Box Tachometer - Step 4.
4.
Connect black multimeter lead to a known good ground.
5.
Note multimeter reading.
CONDITION/INDICATION
Are 22 to 28 VDC measured at white wire on cab control box tachometer?
DECISION
No - Go to step 7. (Step 7 - Are 22 to 28 VDC measured at UPIK harness connector pin U?)
Yes - Go to step 5. (Step 5 - Are less than 200 ohms measured on black wire at cab control box tachometer to
known good ground?)
STEP 5
Are less than 200 ohms measured on black wire at cab control box tachometer to known good ground?
1.
Push in EMERGENCY STOP switch to off position. (TM 5-3825-270-10)
2.
Disconnect batteries. (WP 0085)
3.
Set multimeter to measure continuity.
4.
Connect red multimeter lead to black wire at cab control box tachometer.