CHECK ENGINE LIGHT (CEL) ON AND NO HISTORICAL OR ACTIVE CODES DISPLAYED ON DDR.

TM 9-2320-364-20-1

2-13. DDEC II TROUBLESHOOTING (CONT).

CHECK ENGINE LIGHT (CEL) ON AND NO HISTORICAL OR ACTIVE CODES

DISPLAYED ON DDR.

INITIAL SETUP

Tools and Special Tools

Equipment Condition

Tool Kit, General Mechanic's: Automotive

Engine OFF, (TM 9-2320-364-10)

Parking brake applied, (TM 9-2320-364-10)

DDEC Repair Kit (Item 15, Appendix G)

Wheels chocked, (TM 9-2320-364-10)

Reader, Diagnostic (Item 53, Appendix G)

Top engine access cover opened,

(TM 9-2320-364-10)

References

TM 9-2320-364-10

START

KNOWN INFO

TEST OPTIONS

Is CEL erratic or intermittent

Suspected DDEC Fault.

Visual inspection.

when engine is running at

2100 rpm?

REASON FOR QUESTION

POSSIBLE PROBLEMS

Erratic or intermittent CEL (with

Short in CEL diagnostic request

erratic engine operation)

line wire 451.

indicates short to ground on

Short in CEL driver line

diagnostic request line

wire 419.

wire 451.

Damaged harness connectors.

Repair wire 451 (see

schematic Fig 2-1)

or notify DS

Maintenance.

Verify repair, go to

Step 4 of this Fault.

YES

2-150