STEP/SEQUENCE
RESULT
WHAT TO DO NEXT
TM 9-2320-363-20-1
Section 4
TROUBLESHOOTING CHARTS
E.
FLASH CODE:
42
J1587 CODE:
S21 1 - TOO MANY SRS (MISSING SRS)
42-13
Check TRS Connectors
Check connectors at Timing
Connectors
Replace Timing Reference
Reference Sensor (both harness
are okay.
Sensor. Then go to 42-14.
side and sensor side) for
damage; bent, corroded or
Problem found.
Repair terminals/connectors
unseated pins or sockets, or bad
Then go to 42-30.
contracts.
42-14
Verify SRS/TRS
Turn ignition off.
(No Codes).
Repairs are complete.
Reconnect all connectors.
Clear codes.
Code 21/1 reappears
If TRS was just replaced, go
Start and run engine until
(and any other codes.)
to 42-7. If the TRS was not
"Check Engine" light comes on
replaced, go to 42-6.
or for 1 minute.
Stop engine.
Read inactive codes.
Code(s) other
Go to START-1, pg 3-345.41,
than Code 21/1 received.
to service other codes.
42-15
Verify Cranking
Voltage
Connect all connectors.
Engine starts.
Replace battery. If a voltage
Turn ignition off.
equalizer is installed, check
Wire a 5-pin power connector to
operation of equalizer. Indications
fully charged battery (12 volt).
are equalizer is not working.
Connect to ECM.
Then go to 42-30.
Try to start engine.
Engine does
Replace ECM, then go to 42-30.
not start.
Change 3 3-345.329
