Immobilizer –DTC Troubleshooting Data
Version: 1.
2
Date:
03-June-2014
Prepared Author
:
Sarang K/Mithipati P
Review & approved by
: R A Rode (ERC-E&E)
Page: 29 of 67
Copyright ©
TATA MOTORS Ltd.
This document must not be used in any way, such as copying and redistributing to third parties, without the consent of author.
P0604 - 00:- Internal Control Module Random Access Memory (RAM) Error
Overview:
ISO Code
P0604 - 00
Customer Symptom
None
Fault Effects (On Vehicle)
N/A
Lamp Status (If Any)
None
Fault Detection Condition
Memory integrity check for RAM
Normal Operating Condition
Normal operating range:
ECU will be awake from 6V to 16 V.
Full assistance is b/w 11.5 to 16 volts.
Reduced assistance is b/w 9 to 11.5 V
Probable Trouble Area
VICM internal damage
Healing Condition
N/A
Component Details:
Immobilizer system is designed to prevent vehicle theft by electronically disabling the engine starting system. The
engine can be started only with vehicle’s original immobilizer ignition key, which has an electronic identification
programmed code. Immobilizer unit is an add-on part on the ignition switch, fitted on the steering column. The
engine can be started only with the vehicle’s original immobilizer ignition key. The electronic key communicates
the identification code to ICU when the key is turned to the "Ignition ON" position.
Preliminary Checks:
1. Voltage at the battery terminals should be greater than 11.5V.
2. VICM power supply connector should have greater than 11.5V for full assistance.
3. Check battery cable and VICM connector terminals for damage.
4. Check VICM ECU for pin bend/damage.
5. Alternator output voltage should be between 13.5 V to 14.5 V in engine running condition.




