247 REMOTE COMM ERR
CALL SERVICE
Description
The Master Controller has lost communication
with the Remote Module.
Probable Causes and Test Procedures
- Ensure the remote module has power (24V ±15%
on wire #285C).
* If power not present at aft handle, trace wire
#285C back to the over-the-mast cable.
- If connection is good, but still no power, check
over the mast cable connection to main harness.
- If connection is bad, replace reach harness.
- If mast connection is good, but no power,
check wire #285 from IFB.
- If main harness connection is good, check
FU13 on IFB.
- If fuse is good, replace IFB.
* If power is present, move onto the next check:
- Measure CANbus impedance with truck off and
battery disconnected.
* CAN should be 60 Ohms between wire #900
and #901 at diagnostic connector.
* If CAN impedance is 110 Ohms or greater,
there is a broken CAN line to the remote:
- Check wire #900 and #901 on the over the
mast wire.
- if either have no continuity.
- Replace reach harness if continuity bad or
shorted to B+ or GND.
- If a good connection exists, check wires #900 and
#901 on reach harness through mechanism.
* If connections have been good, check harness
& connector pins for continuity. Repair as necessary
* If no faults in harness found, replace remote
module.
- NOTE: Usually a bad harness or lack of power to
module is the cause.