TM 10-3930-675-24-1
TRANSMISSION SPEED SENSORS TROUBLESHOOTING - CONTINUED
0027 00
NOTE
Refer to WP 0004 00 for additional troubleshooting guidance, information, and illustrations that
locate critical components.
Refer also to illustration at end of work package for component location.
Table 1. Error Code 649 - Engine Speed Sensor Failure,
Open Circuit or Short Circuit to Battery Troubleshooting Procedures.
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
If resistance is not as specified,
Open Circuit or Short Circuit to Battery.
connector X173 located in the
move the cab to the transport
middle panel behind the
position (TM 10-3930-675-10)
operators
seat.
Check
and remove the transmission
resistance at the loose part of
front access cover (WP 0142 00).
connector X173 between pins
4 and 5 (WP 0048 00-14).
Resistance should be 950 to
1,150 Ohms.
2. Check resistance. Disconnect
If resistance is not as specified or
and inspect the 761 engine
the 761 engine speed sensor is
speed sensor located on the left
damaged, replace the 761 engine
side of the transmission. Check
speed sensor (WP 0094 00).
resistance of the 761 engine
speed sensor between the two
pins (WP 0048 00-14).
Resistance should be 950 to
1,150 Ohms.
3. Inspect the 761 connector and
If continuity is not present in
pins for damage and proper
either wire or connector 761 is
connection. Check continuity
damaged, notify Sustainment
of wires 1734 and 1735 (WP
Maintenance to replace engine
0048 00-14).
and transmission wiring harness.
4. Check connector and pins. a. Repair or replace damaged
Disconnect ECU (793). Check
connector (WP 0113 00).
the connector and ECU pins 3 b. Replace damaged ECU (793)
and 19 for damage. Check
(WP 0080 00).
continuity of wires A1734 and c. Replace open or shorted wire.
A1735A (WP 0048 00-14).
0027 00-2
