ENG5V - ENGINE HARNESS +5 VOLTS SUPPLY

TM 9-2320-364-20-1

2-14. DDEC III/IV TROUBLESHOOTING (CONT).

Section IV. TROUBLESHOOTING CHARTS (Cont.)

E. ENG5V - ENGINE HARNESS +5 VOLTS SUPPLY

NOTE - This chart is only to be used if:

1) All basic mechanical checks and physical inspections have been performed with no problem found; and,

2) Diagnosis of DDEC III/IV was started at step START-1, pg 2-539, and you have now been referred here.

STEP/SEQUENCE

RESULT

WHAT TO DO NEXT

ENG5V-1 Check for Low

Battery Voltage

Was there also a Code 168/1?

Yes.

Go to 46-1 (page 2-719).

No.

Go to ENG5V-2.

ENG5V-2 Check for + 5 Volts

Turn ignition off.

Between 4.7

Voltage reading is correct. Check

Disconnect the Oil Pressure

and 5.2 volts.

voltage at next connector. If all

Sensor (OPS) (para 7-68) and

connector voltage readings are

Turbo Boost Sensor (TBS)

correct, go to ENG5V-3.

(para 7-63) connectors.

Turn ignition on.

At each sensors harness

Less than

Go to ENG5V-4.

connector, read voltage between

4.7 volts at any

socket C (red lead) and sockets A

or all connectors.

(black lead).

Greater than

Go to ENG5V-6.

5.2 volts

at all connectors.

ENG5V-3 Check ECM

Connectors

Check terminals at the engine

Terminals and

Replace ECM (para 7-57).

harness connector (both the ECM

connectors are okay.

Then go to ENG5V-30.

and harness side) for damaged,

bent, corroded and unseated pins

Problems found.

Repair terminals/connectors

or sockets.

(para 7-101). Then go to

ENG5V-30.

2-761