Sooo, this didn't pop up until I replaced the engine harness with a custom one to link a ProEFI 128 and Stock ECU.
No issues starting, car runs fine.
I could only find info about the security light flashing and not allowing the car to start. Didn't find anything about the light blinking while driving. I'm not too savvy with the immobilizer system as a whole... yet anyway.
I'm thinking about just pulling the bulb out of the cluster but want to make sure I'm not going to cause any ill effects by not taking care of this if it's an actual issue.
-I should note that I recently found a loose wire in the new harness. It was causing my tach to stop working accompanied by bogus low oil level, rear lamp and ABS warning lights. I soldered the wire and all those issues were resolved but the security light continues to flash.
Sorry I can't give you any thoughts. I'm not 100% on this subject. Maybe there's a wire missin on the custom slang you got made that's triggering it? Have you counted the wires and looked at pinouts? That's the first step I would assume. Just putting another prospective out there, sorry I can't help. Where did you get your ecu and harness system from? Im thinking of getting a proefi128
I'm thinking the same thing. Could just be another harness issue. May just pull the bulb once I get tired of seeing it flash.
I had a full engine harness with both ECU provisions made by Tweak'd. It's not a patch style harness.
HOWEVER, If you are planning on going with the 128 and your car is 02+, I have a brand new harness that plugs in like a patch for cheaper than any dealer will sell it to you! It's posted in the marketplace somewhere
I'm getting closer to taking the car out of storage for good. The security light continues to flash when driven for monthly warmups. The light is never solid.
Last ditch effort for any ideas. If no one has any thoughts, I'll just pull the bulb. The immobilizer is probably bypassed anyway.
I dunno... one of the wires between ignition and ECU or transponder/receiver? Or maybe its just looking for a reference signal from igniter or something that is no longer there. i.e. they cut a wire maybe should have been teed? The immobliser seems to feed back to main ecu which means it could look for a number of things.
Quickest solution is what you are hesitating to do with the light bulb.
one of the only other things related to flashing was while in programming mode, but not sure how you could cause it to stick in that mode
If a wire fell out of the harness, I would run a quick continuity test on the harness to make sure none of the pins in the connector housings are shorting or bridging. Its possible (with a weak connector wall) that we could have some bridging or arching going on?
Wish I had an electrical diagram and pinout sheet for you. This would be my first step prior to simply pulling the bulb.
Also, it may be rather trivial but:
Make sure that when you solder all the wires down that they are electrically wrapped or heat shrink to avoid any shorts or electrical bridging.
Again, I would run a continuity test of the connector (LEXUS END) and test of connector (Custom Slang End) and ensure there arent any issues with the harness and pin location voltages line up.
Unfortunately the output for the light is from the ECU... meaning the ECU can take many different signals, do an internal calculation or 100 of them and then decide to activate the light. The wiring pin out sheet for the security light/immobiliser is basically all things going to the stock ECU and then the output of the light. It really needs to be accompanied with a description on all the things that would activate it to trace it down quickly. Otherwise removing the bulb really is the easiest thing to do since it will take a few minutes.
Now knowing more of what's involved, it doesn't sound worth my time to diagnose. I didn't realize it was tied to so many things... I'm sure most of which have been replaced or removed anyway.
I'm afraid if I go through all the steps, everything will check out fine and I'll be left without a solution OR I'll find the problem and it's something that can't be fixed and I should have just pulled the bulb to begin with. Haha
Hey, I just stumbled across this thread after a quick Google search. I just finished installing a custom Tweak'd harness as well (but mine is for the Series 2 AEM) and am having the exact same issue. My security light continuously flashes even with the engine running and it's pretty annoying. It seems as though Tweak'd is missing something with our harnesses in order to keep the security system happy. Like you, I may just pull the bulb as a quick/temporary fix until I can figure out what the real issue is.
Does your keyless entry work at all? Mine doesn't seem to be working at all.
Sup Man! You were the one that helped me out with the patch extension harness. :approve: Ended up going with the current custom harness.
I wonder if we should both email Tweak'd at the same time and see if they can help!
I'll check on the keyless but pretty sure it worked last time I took it out.
P.S.: Had to repin a lot of stuff like the ignitor and program the #6 injector to run "backwards."
Thankfully I had a genius by my side during the install and initial tune.
Later I found and corrected a loose connection in the ECU harness. It was causing the oil light and ABS light to come on intermittently along with the tach not working:
Yeah I have already had to deal with my fair share of issues with this new harness as well. My entire harness was built 15" shorter than I specified, the front knock sensor lead was 3-4" too short (had to extend it), they used the wrong coolant temp sensor connector, etc. Luckily I haven't found anything that was pinned incorrectly...yet.
Maybe it's just coincidence that my key fob battery died or something, but I can't get the keyless entry to work at all now. I guess I'll have to replace the battery and try again.
Ha - I had those same issues as well. My stock ECU was supposed to tuck under the seat and the ProEFI was supposed to go under the dash. Instead, I had to put the stock ECU under the dash and the ProEFI in the glove box being the harness was too short. They also gave me the wrong coolant temp connector but was able to repin the stock connector in it's place. My knock sensor leads were ok but had to extend the intake temp sensor lead.
Let us know about the keyless - Not sure when I'll get a chance to check mine.
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