1996 LS400 fitted with Scorpion 5000. Remote control fob reset help required please

[Howplum]

After several months of dithering I have now bought a friend's car which has been sitting unused since 2017. It has several issues, which will become the subject of a separate thread, but for now my main problem is how to turn off the immobiliser so that it will start.

I know it runs because in October last year I posted a tutorial on how to reset the alarm/immobiliser, but at that time the remote control was working.

Since October the car has had no Battery in it, although at some point earlier this year a mechanic did start the car without any apparent problem.

However, having now bought the car I find the remote control is not communicating with the alarm/immobiliser, so does not operate the central locking or activate/deactivate the immobiliser.  This is the type of remote control I have:

I have tried the following reset procedure, several times, which seems to be the most common method for this system:

1. Disconnect Battery

2. Turn ignition key to "on" position

3. Reconnect Battery

4. Press black button on remote for 10 seconds (presumably with the ignition key still in the "on" position)

I have tested the Battery in the remote, which is perfectly healthy.

Is there another reset procedure for the remote that I could try?

[steve2006]

Not sure if the process is the same but on the later LS400 the ignition needed to be left on for around 10 minutes to remove the security light before the engine would start.

[Malc]

this is not the same remote fob I have for my October 1995 car !

Malc

[Howplum]

Thanks @steve2006. That was the procedure the dealer gave me last year, which didn't work at the time, but it's worth trying again.

[steve2006]

I have found this.

 

 

[Howplum]

Thank you @steve2006. That could be useful, but my immediate issue is to get the car started so that I can get it onto a low loader and brought to my home.

[Tulpen]

Back in my 400 days, my car would be left for a week or so in airport carparks. The Battery would go flat and, when I opened the car with the key, it would think I was trying to steal it and refuse to start. I found a way to fool the system and it is detailed in this old thread:  

I hope this helps.

BTW, I had the same key fob as you.

[Howplum]

Thanks for that @Tulpen, that might come in useful.

In fact I have just found the original operating instructions for the security system, which, under the heading "Failure to Disarm", states that a random rolling encryption code is used, so occasionally the remote and the system will become out of synchronisation.   The solutions, which sound  easy, are:

1. Press and hold the ON/OFF button for 10 seconds, which should resynchronise the system. Pressing the ON/OFF button a second time should then disarm the security system.

Or:

2. If that fails, contact your Lexus dealer!

[Howplum]

I have now tried nine different reset procedures, none of which have enabled the remote control to communicate with the alarm control unit.

I think I might have to admit defeat and call in a professional. Not a great start to Lexus ownership, but hopefully from here the only way is up.

[Malc]

might an auto electrician be able to support you ?

Malc

[Howplum]

In the end I admitted defeat and found an auto electrician who has removed the offending alarm/immobiliser for a reasonable £45. It took him an hour, and he was a professional, so goodness knows how long it would have taken me, had I even been able to figure it out.

He was surprised that the system had lasted 24 years, since apparently Scorpion did not have a good reputation for reliability, especially once over 10 years old.

It does mean I don't have the same level of security, or remote central locking, but the insurance company don't seem concerned. Still, at least I can get it onto a low loader and back to my house.

Let fun begin.........