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'02 MR2 Anti-theft/Immobilzer

7.8K views 15 replies 2 participants last post by  merryfrankster  
#1 ·
Car battery died and tried to jump off. I am guessing that system "active" when car died, so when I get in (top down/unlocked door from inside) I triggered it. Alarm was going off while trying to jump and would not start. I have key and fobs. I got a new battery and now it won't start. Will crank but not fire, seems either fuel pump or something wont send fuel to get going. For whatever reason, the fobs nor key in the ignition are disabling anything. I am not sure what is going on? Any help would be very appreciative.
 
#2 ·
The anti-theft system is not factory, it is dealer install. You can get in under the dash and remove it. It is a very clean plug and play harness install, unlike stereo shop rat's nest installs. Should be pretty obvious what it is, if you have ever dealt with auto electronics. It goes on the ignition wire loom that comes up under the steering column. If you remove the anti-theft, you will still have the immobilizer, which is factory feature, integral in the car's ECU. By the way, make sure that you are using the transponder key, not a spare key. When you try to start the car with a non-transponder key, the kind you get at the key desk at Wal-mart, the engine will crank, but not fire. That's the behavior of the immobilizer: starter operates, but no spark or fuel. The behavior of the anti-theft system is different:it disables the crank entirely, starter will not operate. So this means, if you are getting a crank, starter is operating, you are getting past the anti-theft system, but something is amiss. I am attaching a couple of reference documents for the anti-theft system, maybe you will find something useful in there. And it seems to me, from dealing with malfunctioning anti-thefts a few times, that if your battery is not at 100% charge, this will trigger the anti-theft. So either charge it, or replace it - oops I see that you have a new battery, never mind. Also check that you have not blown any fuses while jump starting your car. This could also make the anti-theft do weird things. Also, try disarming the alarm by turning the key in the door lock. This is the method suggested in the documentation. I don't know if any of this will help, I usually end up just ripping out the system.
 

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#3 ·
@merryfrankster thank you for that. After reading what you put, it definitely seems more like immobilizer than anti-theft. The key fobs will do the following:
Press panic and alarm goes off
press unlock and it beeps/lights flash but doors do not unlock--this is the same for the lock button as well.

I will check fuses as well.

If it is immobilizer what are the options? Thanks again
 
#4 ·
Here is how the immobilizer system works on the Spyder:

The authorized key codes for your car are stored on a small chip on the ECU motherboard. The transceiver/antenna on the ignition lock reads the key code from the transponder key and sends it to the ECU. If there is a match, the engine can fire. Otherwise, it just cranks.

You can verify whether you are having an immobilizer issue by checking the status of the immobilizer system with a consumer version of Techstream, the Toyota diagnostic software. This is also available on professional level scantools like Snapon or Autel.

You can also check the status of the immobilizer system by the red led light above the center of the climate control. When you insert an authorized key in the ignition, and the key is recognized, this light should go from flashing to indicate immobilizer on, to off, to indicate immobilizer off.

If your immobilizer system needs to be reset and reprogrammed, there are three ways to do this:
1. Use a dealer version of Techstream to reflash the immobilizer chip (this means you take the car to the dealer on the back of a tow truck).
2. Remove the ECU, open it, and re-flash the immobilizer chip, using consumer-grade chip-burning tools from Amazon.com. There are detailed how-to's on this.
3. Find an authorized locksmith who can reflash your immobilizer. Some can, most can't.

I should add, there are a few independent service providers who will perform option 2 for you if you send them your ECU. For example, Wiregap corp.

It is extremely rare and almost unbelievable for the immobilizer system to reset itself spontaneously. I know of only one situation where this may have happened, although it is not entirely clear what actually happened.
 
#6 ·
So I found one problem. The fuse #42 in engine compartment was blown (Multi-port injection, engine immobilizer system). I switched it with another one (#39) and it started up. Now however, none of the dash gauges read (RPM/FUEL/MPH) no clock/radio, etc...But it is starting and running!!
 
#12 ·
No unhooking the battery will not fix anything. Here's two documents. Power Source tells you how power flows to every device through every fuse. Relay Locations tells you where every fuse is located. Start with your radio, that you say is not working, or anything else that is not working, and work back from there.
 

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#13 ·
I am stuck. I checked every fuse and all were good. I believe it has something to do with the entire R/B No. 3. All of the fuses are good and I switched the relay 12V with the one in J/B 1 and both worked so it isn't relay related to the panel either.

But everything I am missing is connected to that box
1. Power Steering
2. Gauges
3. Radio/Clock
4. A/C
5. Power Winows/Locks
6. Tail Light/Brake lights

Sure I am missing others.
 
#15 ·
After I posted last night I looked over the stuff you sent again and it was directly connected to that 100A fuse. Sure enough it was easy to tell it was blown. The video you posted made it EASY to take care of. Thanks for all the help. Saved me $$.