P174 4 - FUEL TEMPERATURE CIRCUIT FAILED LOW (LOW VOLTAGE)

TM 9-2320-364-20-1

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

Section IV. TROUBLESHOOTING CHARTS (Cont.)

E. FLASH CODE:

J1587 CODE:

P174 4 - FUEL TEMPERATURE CIRCUIT FAILED LOW (LOW VOLTAGE)

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

24-1

Multiple Code Check

Were there any other active

No other codes.

Go to 24-2.

codes besides Code 174/4?

Yes, any or all

Go to VEH5V-1 (page 2-767).

of the following codes:

110/3, 175/3, 174/3,

102/3, 187/4, 91/4, 100/4,

102/4, 110/4, 175/4.

Yes - but none

Go to 24-2.

of the above.

24-2

Sensor Check

Turn ignition off.

Code 174/3 (or any

Go to 24-3.

Disconnect FTS connector

other codes except

(para 7-62).

Code 174/4).

Start engine and run

(TM 9-2320-364-10) until "Check

Code 174/4 (and any

Go to 24-4.

Engine" light comes on or for

other codes).

8 minutes.

Read active codes with engine

still running.

24-3

Check FTS Connectors

Inspect terminals at the FTS

Terminals and

Replace FTS (para 7-62).

connectors (both the sensor and

connectors are okay.

Then go to 24-30.

harness side) for damage; bent,

corroded, and unseated pins or

Problem found.

Repair terminals/connectors

sockets.

(para 7-101). Then go to 24-30.

24-4

Open Line Check

Turn ignition off.

Less than or

Signal line (ckt #472) is shorted

Disconnect the engine harness

equal to 10,000 ohms

to the return line (ckt #452) or

connector at the ECM.

on either reading.

battery ground. Repair short.

Read resistance between sockets

Then go to 24-30.

R3 and Y2 on the engine harness

connector.

Greater than

Go to 24-5.