Possible to disable immobilizer

[ecmbuster]

The answer is YES you can disable the Immobilizer within the ECM with rewriting the bin file.

[caldirun]

http://wiki.ross-tech.com/index.php/01176

01176 - Key Faulty: Signal too Low

Possible Causes

• Low voltage in key-battery
• Bad connections between immo reader coil and immo control module

Possible Solutions

• Replace key-battery
• If more than one key acts like this, check / clean the connector between immo reader coil and immo control module, the contacts tend to oxidize
• There is also another known issue with the wiring between reader coil and immo module, they are known to be too short so there is a 'longer' wiring (8D0-972-275) available

I quote this from Ross-Tech Wikki, but I am puzzled as to how a low remote fob battery can affect the immobilizer?

[ecmbuster]

The members at Ross-Tech Wiki, could have "misquoted" another piece of information. Members that have access, can edit that mistake. We all know that the battery within the remote, is strictly for Central locking (address 35) or Comfort control (address 46).

The issue with the reader coil is valid, the wires have disconnected or had higher than normal resistance causing this fault within the Immobilizer. The first test is checking the coil. Testing the key(s) is the next test reading block 022 at the Instrument cluster (address17) There, you'll see if the key(s) is authorized, ECM response, Key(s) response and adapted keys.

If the Immobilizer is suspect, disabling the Immobilizer within the ECM is a good test. That doesn't mean that the instrument cluster isn't suspect either. Unfortunately, that procedure can't be accomplished with the cluster.

[ecmbuster]

Adding to the battery. If the vehicle battery is low and if the vehicle key was ON and the key was NOT recognized because of a low voltage issue, expect that fault. Another problem is when stater current draw is higher then specifications. That fault would be produced because of the same situation, low battery voltage. Low system voltage is not tolerated in the CAN and Immobilizer system. The worst mistake by vehicle owners and repair facilities is to "boost" or "jump" start the vehicle. High current and voltage spikes are again not tolerated and expect controller damage if continued. The simple way out of that situation is a "booster pack" attached to the system battery for 20 to 30 minutes the "equalize" system voltage. The best way is to replace the vehicle battery but still having the "booster pack" attached to the electrical system. That way, none of the customers "adaptations" are lost and vehicle programming is minimized.

[greeny122229]

I had one of my customers asking this very same question last week. If you could disable the immo at any given time, it wouldn't be much of an immobiliser TBH...

you're better off addressing the issue rather than trying to simply de-activate it.

another thing to bear in mind, is the impact this may have on your insurance, many companies consider their insurance void if a vehicle is fitted with an immobiliser which fails to function

it is possible... and takes roughly 1 - 30 mins - only works pre 2001 though

[abcd1234]

Adding to the battery. If the vehicle battery is low and if the vehicle key was ON and the key was NOT recognized because of a low voltage issue, expect that fault. Another problem is when stater current draw is higher then specifications. That fault would be produced because of the same situation, low battery voltage. Low system voltage is not tolerated in the CAN and Immobilizer system. The worst mistake by vehicle owners and repair facilities is to "boost" or "jump" start the vehicle. High current and voltage spikes are again not tolerated and expect controller damage if continued. The simple way out of that situation is a "booster pack" attached to the system battery for 20 to 30 minutes the "equalize" system voltage. The best way is to replace the vehicle battery but still having the "booster pack" attached to the electrical system. That way, none of the customers "adaptations" are lost and vehicle programming is minimized.

OK, so I'm guilty. I have replaced the battery on my 1995 A4, and now the immo light is flashing and won't let me start the car. Any suggestions would be gratefully recieved.

[Ashley231]

it is possible... and takes roughly 1 - 30 mins - only works pre 2001 though

Can i know how the immo on av Vento 1997 can be disabled.

[andyred]

great help

[Ashley231]

Can i know how the immo on av Vento 1997 can be disabled.

Thanks greeny....
But how can i disable it....
please help me.

[Theresias]

Thanks for the hint ecmbuster, not sure why we never corrected that page. Went over it again and made a couple of changes/additions which should make things clearer now.

http://wiki.ross-tech.com/index.php/01176

BTW: Personally I think disabling the immo is a waste of time and efforts, immo problems are easy enough to diagnose using proper tools and the data provided by the immo itself.