This post is the followup for the one I posted in page 135/136 of this thread (last post
http://www.team-bhp.com/forum/1856618-post2031.html).
This issue was mainly on the random service light behaviour.
1) After my last post (in April) I had to fight with TASS and Tata customer service engineer both in emails and in person to consider this as an issue.
2) I refused to
a) agree with their "song" saying that this is a fuel problem
b) agree to close the job card open at that point of time.
3) I wanted them to take back the vehicle at premium cost as TML did not know what the problem is and as they had to learn from my car.
4) I asked TASS to open a ticket at TML factory (TASS mentioned that they had already done so)
3) This made Tata service engineer active and he mentioned that at no condition the car will be taken back and he could arrange everything (including changing engine?) to get this problem out. (FYI he is on this from Nov 2009 - and he said that only TASS folks were concentrating that time :-()
4) The car was taken for service and they recorded (n th time) the details of the car/ECU status to send to Pune factory (as per Customer engineer). Also at this time they(TASS) said that the service light appeared during their drive (i.e. they could reproduce this issue). The car was sent back.
5) After a week the car was again called for service. After a day I was called explained about the root cause and fix of the problem (detail below seperately)
6) I asked for 3 months time for me to confirm the fix and I was given.
7)Till date the problem has not come and I completely feel the problem has been fixed (As otherwise I would seen that 30 to 50 times minimum according to frequency I used to get)
Details of problem:
I use to get the "service light" with error code "accerlometer error" randomly most at the cold/high traffic conditions.
What is accerelometer doing under bonnet:
Accelerometer detects the "knocking" feeds back to ECU to alter the fuel parameters. This works on vibration pattern of the engine.
What is accelerometer error:
This says that accelerometer does not give any signal (dead) or gives incorrect signal.
Details of root cause:
1) As I have mentioned earlier they had already changed the accelerometer. Hence "dead" accelerometer is ruled out. The other option is incorrect noise sensed from engine.
2) The culprit was "valve tappet timing". Because of incorrect timing/clearance, unwanted noise (physical noise) has been triggered which in turn has raised incorrect accelerometer signal. This signal coould not be appreciated/correlated by ECU as "knocking" ( because the signal will not correlate with fuel injection timing).
Details of Fix:
Very simple. Adjusted timing and clearance of valve tappets.
So now both my safari and myself are happy

with improved mileage and improve performance (that what I experience before).
Finally,
1) The big battle took long time and I got the fix in the end of June 2010. I recently (1 month back) confirmed TASS that my issue can be closed.
2) I deeply apologize for being late to inform the community (as I always had a reason(health or work pressure) to procastrinate the posts - both this one and the earlier ones). Sorry again for that. I thank you all for your support and ideas I got.
3) As my car lease with my company has ended seriously think to go for new car lease. Mostly Fortuner?. Soon I will post the sale ad in ad section for my car.
Thank you,
Vichu