How To:- Pair a Transponder Key with a MK2 rev 4/5 MR2

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I've spent a few months (obviously not at the one time) researching the various bits of this - from the key blade, to the chip type, etc..I already had a spare purchased [overpriced IMO] from a local locksmith but wasn't happy with its clumsy look and found that the mk3 owners has successfully programmed keys themselves.

Before I go into all the boring bits, and all I've researched and found I'll post the quick fix to works 100% with 99/00 mk2 sw20 MR2 Revision 5 but should work with the Rev4 (and possibly Rev 3's)

A perquisite is that you have the black master key for this, if you've only got the grey key it's a no go. :(

Here is the key pair programming instructions:

Turning the ignition to on does NOT MEAN TURNING OVER ENGINE unless stated below.

NOTE: Contrary to what Toyota states, the security LED on the dash didn't come on and there was no notification that the pairing was successful, just the new key now starts the car

Starting Conditions:
-Vehicle Unlocked
-All doors closed
-No key in igntion lock

Insert a programmed black master key (Current Key) into the ignition lock

Carry out the following within 15 seconds:
Turn the igntion on/off four times
Turn the igntion back to on (fifth time)

Carry out the following within 20 seconds:
Open & close the drivers door six times

Carry out the following within 10 seconds:
Remove the key (working one) from the Igntion lock

Carry out the following within 10 seconds:
Insert the key to be programmed into the ignition lock (NEW KEY)
Turn the Ignition lock on and leave for at least 80 seconds.

Remove the key from ignition lock.

Open and close drivers door to complete the process (IMPORTANT)

I Got the 4C Key (TOY41 Blade) for $10.50 Delivered from the below seller on aliepxress


The Locksmith -vs- Toyota -vs- The Clone




There are 2 keys available from Toyota Directly:



89786-17020 - TRANSPONDER KEY SUB (Valet ???????)

Both are the same price but the sub I'm guessing doesn't open boot or has access to program further keys!

The Boring Stuff (about the immobiliser):


System Diagram


System Location (rough guide! [for mr2] )


Toyotas Take on this:


...a reason why the door switch is crucial to this process


...and thats it !

I have a 51 page PDF from the Toyota workshop dedicated to the engine immobiliser (troubleshooting, etc) I found on the net after much much searching.

Click here to download it:

engine immobilizer.pdf


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