2001 Sequoia Immobilizer / key cylinder

Hi Folks, I installed directed/avital remote starter in this truck yesterday and have an issue with the immobilizer.

First I was having problem with not disarming, I think to do with the disarm signal (wired to keysense at cylinder) is pulsed by the box, when the truck needs constant ground. So I wired status output to keysense so it gets held at ground whenever box is running the car. Fixed

For testing purposes I just zip tied the master key 2 to the cylinder and that seemed to be working fine. It would start, I could insert master key 1 and take-over. Drove around yesterday with that method.

Today it was getting crank/no start so I assumed the MK2 moved out of range of the antenna. I pulled off panel and poked around, and tried again.

The real issue now is the cylinder is not accepting any keys. I can't turn it to ACC even. It is not the steering lock, I can lock and unlock the steering, but the key will not turn to ACC.

here are some test conditions:

I can remote start the car by holding MK1 at the ignition.
I cannot remote start by holding MK2 at the ignition. Cranks for .5 second and stops
When I insert MK1 into the cylinder the immobilizer light stops flashing.
When I insert MK2 into the cylinder the immobilizer light goes solid

I also have a valet key but don't know what difference that would make.

I have driven the car with both keys in the past.
It has locked like this once in the past when I left it at the shop with MK2, then picked it up later that day with MK1. It seemingly reset after some period and I was able to start with MK1 again.

Is the car in some sort of lockout tamper mode? I didn't think the immobilizer could freeze the cylinder. Is it coincidence with worn keys and cylinder?



Any thoughts? Please let me know if you need any more data
thanks for your help

I am starting to think the immobilizer is a red herring? Truck has 330k miles so it certainly could be the cylinder. Keys don't look too worn though.

Could be the once a different key is inserted it jiggles something loose so then it locks up? I guess I will pull/inspect/replace the cylinder before continuing troubleshooting.

OK Update. I think we are sorted, thanks for letting me rubberduck debug this thing.

1. Confirmed 01 sequoia needs continuous disarm (-) to keysense, not pulsed from the box. solved

2. Confirmed the ignition cylinder was worn, nothing to do with immobilizer. It's crystal clear now, but had me scratching my head. I bought a new cylinder and swapped it in. with the old I drilled out the pins, undid the circlip and pulled out the inner cylinder. You can see the split wafer pins were worn much more than the solid wafers. I just pulled the offending wafer out and reassembled.





what do the experts think? Should I reinstall the original cylinder with one pin missing and return the new cylinder for $200? It is an 01 with 330k so don't really like spending money unnecessarily... Not worried about the reduction in security.

Re the immobilizer, for testing I zip tied a spare key into the ring and tucked the thing under the dash, not on the ignition at all anymore. Any risk of damaging it this way? pretty much the same as the bypass box except you can hide the key right? Just wondering with the ring not mounted on the cylinder for support if the housing will crack or something.

Let me know your thoughts.