CEL - FIRST CHART FOR DIAGNOSIS OF DDEC III/IV WHEN NO DDR IS AVAILABLE (Cont'd) -726280621

TM 9-2320-364-20-1

Section IV. TROUBLESHOOTING CHARTS (Cont.)

C. CEL - FIRST CHART FOR DIAGNOSIS OF DDEC III/IV WHEN NO DDR IS AVAILABLE (Cont'd)

STEP/SEQUENCE

RESULT

WHAT TO DO NEXT

CEL-4

Verify Code(s)

Turn ignition on.

"Check Engine"

Read codes and follow

Obtain a DDR.

light stays on.

appropriate diagnostic chart

Clear codes.

(see Table 2-19).

Turn ignition off then back on.

"Check Engine"

Note status of "Check Engine"

light goes on for 5

Go to CEL-5.

light.

seconds, then goes out.

"Check Engine" light

Go to CEL-8.

is erratic or intermittent.

CEL-5

Verify Code(s)

with the Engine

Running

Attempt to start and run the

Engine will

Go to Chart 2, pg 2-557.

engine (TM 9-2320-364-10).

not start.

Try to get the "Check Engine" light

on by:

-- warming up the engine

"Check Engine"

Previous codes should be

-- slowly changing the engine

light is off.

regarded as intermittent.

from idle to no load speed.

Go to Chart 1, pg 2-554.

Run engine until the "Check

Engine" light comes on or for

"Check Engine"

Read codes.

1 minute.

light is on.

Follow appropriate diagnostic

code chart, Table 2-19.

CEL-6

Check for Open

Turn ignition off.

Less than or

Go to CEL-7.

Disconnect the vehicle harness

equal to 5 ohms on

connector at the ECM.

either reading.

Install a jumper wire between

sockets C1 and G1 of the vehicle

Greater than

An open exists either in the

harness connector.

5 ohms or open on

diagnostic request line (ckt