Isuzu 4JA1 Workshop Manual page 462

6E-208 Engine Control System (4JH1)
DTC P1614 (Symptom Code A) (Flash Code 56)
Circuit Description
The engine control module (ECM) communicates with
the immobilizer control unit (ICU) to execute immobilizer
function. The ECM sends request signal to the ICU. The
ECM receives response signal from the ICU. Both
communication signals are carried out through the
Keyword 2000 serial data link. If ICU receives wrong
immobilizer response signal from the transponder key,
this DTC will set.
Condition for Setting the DTC
• The ICU receives wrong immobilizer response
signal from the transponder key.
Step
1 Did you perform the Diagnostic System Check-
Engine Controls?
2 1. Install the scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Turn ON the ignition, with the engine OFF.
4. Select the "Immobilizer" in the system selection
menu.
5. Monitor the Diagnostic Trouble Code (DTC) Info
Ordered By Priority with the scan tool.
Does the immobilizer DTCs fail this ignition which
begin with B?
3 Monitor the DTC Information with the scan tool.
Does the DTC fail this ignition?
4 Program or reprogram immobilizer function into the
immobilizer control unit (ICU). Refer to Programming
Immobilizer Control Unit (ICU) in immobilizer
section.
Did you find and correct the condition?
5 Important: Replacement ICU must be programmed.
Replace the ICU. Refer to Immobilizer Control Unit
(ICU) Replacement in the immobilizer section.
Did you complete the replacement?
6 1. Clear the DTCs with the scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Turn ON the ignition, with the engine OFF.
4. Monitor the DTC Information with the scan tool.
Did the DTC fail this ignition?
7 Observe the DTC Information with the scan tool.
Are there any DTCs that you have not diagnosed?
Action
Action Taken When the DTC Sets
• The ECM illuminates the malfunction indicator
lamp (MIL) when the diagnostic runs and fails.
• The desired fuel injection quantity is set 0 mg/strk.
Condition for Clearing the MIL/DTC
• The ECM turns OFF the MIL when the diagnostic
runs and does not fail.
• A history DTC clears after 40 consecutive driving
cycles without a fault. Or clear with the scan tool.
Diagnostic Aids
• Non programmed ICU may set this DTC.
• Transponder key problem may set this DTC.
• ECM with wrong specification may set this DTC.
DTC P1614 (Symptom Code A) (Flash Code 56)
Value(s) Yes

Go to Step 2

Go to Applicable
DTC in Immobilizer
Section

Go to Step 4

Go to Step 6

Go to Step 6

Go to Step 2
Go to Diagnostic

Trouble Code (DTC)
List
No
Go to Diagnostic
System Check-
Engine Controls
Go to Step 3
Go to Diagnostic
Aids
Go to Step 5

Go to Step 7
System OK