STOPLIGHT DOES NOT WORK WHEN TRACTOR BRAKES ARE APPLIED CONTINUED

TM 9-2320-270-20-1

TROUBLESHOOTING - CONTINUED

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

33. STOPLIGHT DOES NOT WORK WHEN TRACTOR BRAKES ARE APPLIED CONTINUED.

Step 6.

Plug in firewall harness plug. Go to first switch (1) on brake valves in engine

compartment. Using multimeter set at 30 vdc, put red probe on wire no. 009 (2)

and black probe to good ground.

If meter reads no voltage, close instrument panel (4-244), and left side

of hood (TM 9-2320-270-10) and notify direct support maintenance.

At second brake valve switch (3), using multimeter set at 30 vdc, put red

Step 7.

probe on terminal for jumper wire no. 009 (4) and black probe to good ground.

If meter reads no voltage, close instrument panel (4-244), and left side

of hood (TM 9-2320-270-10) and notify direct support maintenance.

Disconnect and take out jumper wire no. 005 (5) between first switch and second

Step 8.

switch. Using multimeter set at 30 vdc, put red probe on terminal for wire no. 005

on second switch (3). Have assistant apply brakes. Put black probe on good

ground. Make sure air pressure is at operational level (TM 9-2320-270-10).

If meter reads no voltage, install jumper wire and replace second switch

Step 9.

Using multimeter set at RX1, put probe on each end of jumper wire no. 005 (5).

If meter does not read zero, close instrument panel (page 4-244) and

left side of hood (TM 9-2320-270-10) and notify direct support

maintenance.

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