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 FEW SRS (MISSING SRS)
42-5
Check TRS/SRS Gap
(Note: You'll probably have to
Incorrect gap.
Loosen the screw at top of
remove the ECM to perform this
TRS/SRS mounting bracket
check on 92 Series engines.
(don't touch the two screws that
Bar engine until TRS is over
go into block front end plate
a TRS "tooth" of pulse wheel.
they will affect engine timing).
Tap the front of pulse wheel.
Adjust the TRS/SRS until gap
rearward with a soft hammer (to
setting is correct. Tighten screw.
remove camshaft end play).
(If problem returns, pulse wheel
Install TRS/SRS alignment tool
may be loose or bad). Then go
and check gap. (nominal gap
to 42-30.
0.020" or 0.5 mm).
Gap setting is correct
Go to 42-6.
42-6
Check for TRS Code
Was there also a Code 21/0?
Yes.
Go to 42-8.
No.
Go to 42-7.
42-7
Check ECM Connectors
Check terminals at ECM engine
Terminals and
Then go to 42-15.
harness connector (both ECM
connectors are okay.
and harness side) for damage,
corrosion, and unseated pins or
Problem found.
Repair terminals/connectors.
sockets.
Then go to 42-30.
42-8
TRS Resistance
Check
Read resistance between sockets
Less than or
Go to 42-9.
T1 and T2 on engine harness
equal to 200 ohms.
connector.
Greater than
Go to 42-10.
200 ohms or open.
Change 3 3-345.325
