Honda 2004 Odyssey Service Manual page 1834

4. With the control unit still disconnected, make these input tests at the connector and fuse/relay box socket.
• If any test indicates a problem, find and correct the cause, then recheck the system.
• If all the input tests prove OK, go to step 5.
Cavity Wire
A12 Fuse/relay
box socket
A14
B3 RED/WHT
· and
B4 WHT/RED
5. Reconnect the driver's multiplex control unit to the fuse/relay box, and perform the following input tests at the
appropriate connectors on the back of the fuse/relay box.
• If any test indicates a problem, find and correct the cause, then recheck the system.
• If all the input tests prove OK, go to step 6.
Cavity Wire
O3 RED/BLK
I6 RED
6. If all the input tests prove OK, the driver's multiplex control unit must be faulty. Substitute a known-good control
unit, then recheck the system. If the system works properly, the original control unit is faulty; replace it.
Test condition Test: Desired result
Under all Check for voltage to ground:
conditions There should be battery voltage.
Under all Check for continuity to ground:
conditions There should be continuity.
Adjusting dial Check for resistance between
rotated the B3 and B4 terminals:
There should be 0 20 k
times.
Test condition Test: Desired result
Combination Check for voltage to ground:
light switch There should be battery voltage.
ON ( ) or
( )
Combination Attach to ground:
light switch Dash lights should come on full
ON ( ) or bright.
( )
Possible cause if result is not obtained
• Blown No. 13 (7.5A) fuse in the
passenger's under-dash fuse/
relay box
• An open in the wire
• Poor ground (G401)
• An open in the wire
• Faulty dash lights brightness
controller
at all • An open in the wire
Possible cause if result is not obtained
• Blown No. 10 (15A) fuse in the
passenger under-dash fuse/relay
box
• Faulty combination light switch
• Faulty taillight relay
• An open in the wire
• An open in the wire
22-155