2004 ISUZU TF SERIES Workshop Manual

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ISUZU TF SERIES 2004  Workshop Manual 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E –229
Diagnostic Trouble Code (DTC) P0400 (Symptom Code 3) (Flash Code 32)  
Exhaust Gas Recirculation Flow Excessive Detected
Step Action Value(s) Yes

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ISUZU TF SERIES 2004  Workshop Manual 6E–230 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
9 Substitute a known good EGR EVRV and recheck. 
Was the problem solved?—Go to Step 10Go to Step 11
10 Replace the EGR EVRV. 
Is the action compl

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ISUZU TF SERIES 2004  Workshop Manual 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–231
14 Is the ECM programmed with the latest software
release? 
If not, download the latest software to the ECM using
the “SPS (Service Programming S

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ISUZU TF SERIES 2004  Workshop Manual 6E –232 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0400 (Symptom Code 4) (Flash Code 32)  
Exhaust Gas Recirculation Circuit Short to Ground or Open Circuit
Step Acti

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ISUZU TF SERIES 2004  Workshop Manual 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E –233
6 Using the DVM and check the EGR EVRV power 
supply circuit.  
1. Ignition   “On ”, engine  “Off ”.  
2. Remove the EGR EVRV connector.

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ISUZU TF SERIES 2004  Workshop Manual 6E–234 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
10 Replace the EGR EVRV. 
Is the action complete?—Verify repair—
11 Is the ECM programmed with the latest software
release? 
If not, download t

Page 1607 of 4264

ISUZU TF SERIES 2004  Workshop Manual 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E –235
Diagnostic Trouble Code (DTC) P0400 (Symptom Code 5) (Flash Code 32)  
Exhaust Gas Recirculation Flow Insufficient Detected
Step Action Value(s) Y

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ISUZU TF SERIES 2004  Workshop Manual 6E–236 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
8 Using the Tech 2 or the vacuum pump and check the
EGR valve operation for the following condition
through the small window.
ÅERestrict shaft mov