[Blooming Flower]

Recently, I faced one peculiar problem with my Tata Manza QDJ. At the outset, my car odo is around 1,30,000km. It was lying idle in garage for one week. Few days back, I was trying to start it but it didn't. First, I thought it may be a low battery problem and managed to get a spare battery. But this couldn't start the engine too. The engine was cranking sufficiently with both the batteries. Being apprehensive about other major faults, I called Tata service centre and unfortunately, within 75km radius of my hometown there was no TASS while all other major ASS were there! So it took 6hrs for the expert mechanic from Tata to come to my place and inspect the car.

Initially, as a part of usual diagnosis he checked the relevant relays, fuses and wirings. And finally, found the fuel pump is not working. But when he went to find the connection of fuel pump beneath the backseat he found the pump is ok but it is not working due to faulty connection. Instead he suggested me that he would make a direct connection for the fuel pump operated by a switch; so that for the time being, I can start the car and drive it to the nearest TASS. He did the direct wiring and tested the pump working fine (pumping diesel into the engine). But alas! Again, the engine was cranking but didn't start.



Then he asked me to get some petrol. He put about 500ml petrol directly in the intake manifold of the Quadrajet diesel engine and asked me to crank and press the throttle. The engine started but it lasted only till the petrol given in manifold is not finished. His final effort was futile. He just pointed out that the culprit may be either the high pressure pump or the injector (both are Bosch make). The mechanic left charging me a heavy inspection fee without any fruitful outcome.

Now, after two days, I arranged towing service and the Manza was towed to the nearest Tata service centre.

After two days of giving the car to the ASS, the SA called me and said that I can take the car by paying the bill amount which is around Rs. 25k! To start a car this much of bill amount! Now, the story goes as follows.

The SA said, the car immobiliser is damaged. So they had to change it along with the entire lock set. They had to remove and reinstall ECU and BCM as mentioned in the bill with specified labour charges. Finally, what I got are a pair of remote locking invalid keys (both original ones with remote) along with the old steering lock unit and one pair of new keys, one of which is remote lock/unlock enabled and other is without remote (Minda make).

The car was starting and I took it back under compulsion of my own requirement paying the surprisingly high bill amount.

Now some technical aspects arise when I look into the sequence of events along with the credibility of the TASS.



1. How can an immobilizer be damaged when no duplicate keys or anything unauthorised like this was used to crank the engine?

2. Even if it was damaged for say, can it not be reset by the ASS or the keys couldn't be reprogrammed?

3. Even when the car was being towed to the service centre both the older remote locking keys were working to lock or unlock the car. Even the dashboard didn't display any anomalies with the immobiliser light.

4. Now, with the new set of keys, one is with remote other is simple one. How do both key technically authenticate with the immobiliser system?

5. Yes, indeed, both of them are valid key to start the vehicle. So, the evident question is whether the remote circuit to lock/unlock the car has nothing to do with the immobiliser. Is it?

6. If it is, where the unique electronic code is stored in the normal key to authenticate with the immobiliser?

7. In the owner's manual of Tata Manza, I find the learning procedure of new remote keys with the immobiliser system. Couldn't the same be replicated for my case at TASS?

8. How can a ROM be damaged without any intrusive tinkering with it? It raises a question; was it necessary at all to replace the entire lock set?

9. Earlier Safari owners have reported that if the remote battery dies out and the car is opened manually it won't start. Similar issues are reported here.
This raises two probabilities, poles apart each other:

A. The remote circuit in the key to lock and unlock the car has definite relation with the immobiliser system; else the Safari must not refuse to start if opened manually.

B. The newly given without-remote, normal key for my Manza opens the car manually and the car starts! So, the locking remote does not have any relation with immobiliser system!

10. Now-a-days, most of the cars are coming with smart keys. As per my thinking in connection with the experience of this Manza, each remote key/smart key must operate with two different frequencies and codes, viz. one to unlock/lock the car and another to communicate with the immobiliser system for push button start when present inside the car. Is it so?

11. If these inferences are to be justified with proper logic, it seems that the TASS duped me by invalidating the old lock system while they could reset/reprogram it and charging hefty amount for a new system as well as high labour charges of reinstallation.

12. Last but not the least, if the system cannot be reset, any attempt of theft or using different/ electronically damaged key (unauthorized) would spoil the entire immobiliser system and all the cost comes on the shoulder of the owner, which is completely unjustifiable.



Experts, please pour in with your knowledge and logic for the questions asked.

[sparky@home]

kindly revert if your immobiliser light was flashing and secondly did you check the key battery? If the key battery was dead, then the car won't start, an issue which was faced by me. From what i understand a new immobiliser should cost about 5 grand plus/minus 1, a new key should cost around 1500. Has TASS over billed you? Anyway i will check with the local TASS and get back to you what should be the charge for changing the whole unit.

[Blooming Flower]

The screenshot below shows the immobiliser indicator status in dashboard in different scenarios. None, of them was violated when the car failed to start. Indeed, if it was, the expert mechanic from Tata who came down to my garage in hometown wouldn't overlook it before delving deep into the problem and zeroing down to the high pressure pump and injector. Battery in remote key was in perfect condition, otherwise the car wouldn't get locked/unlocked using the remote key.

If your statement is true, that with a dead key battery the car won't start, how the duplicate normal new key (without remote) is able to start the car?

[sparky@home]

Is your immobiliser display working now, viz flashing when the key is out. From what I know the car won’t start with a normal key, or else the immobiliser has to be bypassed. What was the cost shown against the item in the bill. The service technician here said the immobiliser should be around 6000.

[Blooming Flower]

Yes. It is working as usual now. The cost of the lock set alone as they billed is more than what you have enquired. Of course, labour charge is not included in it. The partial snapshot from my bill is given below.

[GTO]

I just hope you haven't been had - here's a thread link where a weak battery led to all kinds of errors (including immobilizer fault code). You can also see other members owning cars with the same engine (1.3L MJD) reporting the same.

Originally Posted by Blooming Flower

After two days of giving the car to the ASS, the SA called me and said that I can take the car by paying the bill amount which is around Rs. 25k!

Even the cost of parts appears to be unusually high for a Tata hatchback.

How can an immobilizer be damaged when no duplicate keys or anything unauthorised like this was used to crank the engine?

Electrical parts fail without any rhyme or reason .

[Jaggu]

There are two components to the whole remote, one the actual remote which lets you lock and unlock the doors. Second is an inbuilt chip on the key fob, that communicates with the immobilizer module of the car through the sensor at the steering lock. The immobilizer unit then communicates to the ECU and gives it a go ahead to start the engine or not. Usually fueling and ignition parameters would be locked, until the immobilizer unite gives a go ahead. Implementation varies from manufacture to manufacture and even within models.

If there is an issue with immobilizer unit, the same would be shown as error code when you run the scan. In some cars there is warning light in the dash itself which will turn on. Battery in the key fob generally powers only the remote lock function, the immobilizer chip on the other hand is usually proximity sensor, that does not need any power from the key fob.

Failure in immobilizer can be on the sensor at the key, sensor at the lock system of ignition, the ecu module of immobilizer or at wiring. Right way to resolve is, to diagnose which part has failed and attending to it. Easy way would be to replace the whole unit that comes with all the lock, key and ecu module unit which seems to have been the case here.

Technically one could have isolated the issue to the sensors or control module and replaced either one, which would have saved some money.

Hope this helps.

[Car-tya]

This thread couldn't have come at a better time. I am having trouble with starting my car since last Friday and had to tow it to the nearest Hyundai Service Center. The issue diagnosis is still on going and now its pointing to tampering with ECM and bypassing the immobilizer (my assumptions). I don't want to hijack your thread with my woes but the guideline mentioned by Jaggu would be quite useful in my case as well.

[Blooming Flower]

Originally Posted by Jaggu

There are two components to the whole remote, one the actual remote which lets you lock and unlock the doors. Second is an inbuilt chip on the key fob, that communicates with the immobilizer module of the car through the sensor at the steering lock.

Thanks a lot for the technical clarification.

Originally Posted by Jaggu

Technically one could have isolated the issue to the sensors or control module and replaced either one, which would have saved some money.

Hope this helps.

Originally Posted by GTO

Even the cost of parts appears to be unusually high for a Tata hatchback.

Electrical parts fail without any rhyme or reason .

Update:

The entire old lock set along with the key was fitted in another Manza for testing purpose at an FNG. And surprisingly, after remote matching/learning as mentioned in owner's manual the assembly is found to be working!

It's quite unbelievable that TASS didn't at all bother to think in repair/reset way; instead they played a loot game on the customer by changing the entire assembly with a new one. Now, I am going to visit the same TASS and would ask the SA to replace the newer assembly in my car with the older one given back to me. I will pay the labour charges for the refitting. If my car starts (hopefully, it will as it worked flawlessly with another car) the long cherished (mal)-practice of the TASS will see daylight.

Meanwhile, I have written to Tata Motors customer care for buying a workshop/service manual of Manza QDJ. I repeatedly requested different dealerships to fetch one. But none of them obliged. Tata customer service reverted to me with promise of helping me out and provided me the cell number of their customer service manager. When I called him, he also blatantly refused to provide me the same. I wonder where Maruti Suzuki has a separate part number for model specific workshop manual and available to the customer if order placed, Tata plays this hide & seek game. I wrote back to them and awaiting their reply.

[archat68]

Originally Posted by Blooming Flower

Meanwhile, I have written to Tata Motors customer care for buying a workshop/service manual of Manza QDJ. I repeatedly requested different dealerships to fetch one. But none of them obliged. Tata customer service reverted to me with promise of helping me out and provided me the cell number of their customer service manager. When I called him, he also blatantly refused to provide me the same. I wonder where Maruti Suzuki has a separate part number for model specific workshop manual and available to the customer if order placed, Tata plays this hide & seek game. I wrote back to them and awaiting their reply.

I was also trying for a service manual for Tiago and taken your steps and got similar reply. I mentioned them that Maruti provides the service manual and even shown them the service manual for my Swift. But even then they refuses.

You can ask your FNG to order a copy of service manual from Tata. I think they are bound to supply them.

[Blooming Flower]

When it comes to service/workshop manual most of the manufacturers go silent or deal with the customers in awkward ways. Tata Motors is no exception here. But if they deny the customers' request they will refuse FNG also. FNG too will buy as a customer. We don't have a proper part number for that either. The secrecy game with workshop manual is nothing new.

[archat68]

Please see the ruling of competition council of india in this regard.
http://pib.nic.in/newsite/PrintRelea...x?relid=109060

[GTO]

Thanks to Ilango Jupiter for sharing this note!

Hi,

With reference to this thread http://www.team-bhp.com/forum/techni...t-changed.html

The same thing happened in my uncle's Manza. It is a 2010 base model without remote, but with the central locking system. The car will crank, but the fuel wont be supplied and hence it wouldn't start. Problem was narrowed down to the immobilizer and we were charged Rs. 8,500 for the complete lock set. Strange and weird. This happened at around 55,000 kms on the odo.