Section 4
TM 9-2320-363-20-1
TROUBLESHOOTING CHARTS
C. CEL l FIRST CHART FOR DIAGNOSIS OF DDEC-II WHEN NO DDR IS AVAILABLE (Cont’d.)
CEL-7 Check ECM
Connectors
l Disconnect the 6-way, power
harness connector at the ECM.
l Check terminals at both the 6-way
power harness connector, and
vehicle harness connector (both
the ECM and harness side) for
damage; bent, corroded and
unseated pins or sockets.
CEL-8 Intermittent Check
l Note Whether flashing “Check
Engine” light is reading a valid
code or if it’s just erratic.
CEL-9 Check for Short
l Turn ignition off.
l Disconnect the vehicle harness
connector at the ECM.
l Read resistance between pins A
and M of the 12-pin, DDL
connector.
CEL-30 Verify Repairs
l Turn ignition off.
l Reconnect all connectors.
l Turn ignition on.
. Clear codes.
l Turn ignition off.
l Turn ignition on while at the same
time observing the “Check
Engine” Light.
NOTE: Some calibrations will not
allow clearing codes this way.
Obtain a DDR or consult a dealer.
RESULT
I
WHAT TO DO NEXT
Replace ECM. Page 4-192.
Then go to CEL-30.
Repair terminals/connectors.
Then go to CEL-30.
Go to CEL-9.
Go to Chart 1, page 3-136.
the Diagnostic Request line (ckt
#45 1) is shorted to ground (either
ckt #150 or chassis ground).
Refer to direct support.
Go to CEL-7.
Repairs are complete.
All system diagnostics are
complete. Please review this
section from the first step to find
the error.
Go to CEL-1
3-135
