My immobilizer fix (1 Viewer)

[medtro]

thanks, perhaps for the clarification of others who read this thread, is it correct to point out that the E terminal where the original relay was connected and is left out in the pictures here for the solution (ofcourse corrected in your updated kit); E terminal is connected to the BATT node of ECM which requires a constant 12V power. and this error will be resolved by not leaving it emply but by feeding it constant 12V fused power source ?

Please see post #99.

 

[medtro]

I figured I'd someone else stumbles upon other posts they would get the solution too. Thanks again. You're awesome !

There is no need to ask same questions again and again in this thread.

 

[70 FJ40]

I'm sorry if my issue has already been addressed but I'm needing to get my Cruiser going as soon as possible and I'm hoping to get an answer quickly. I will reread the thread throughout the day. I've had the immobilizer issue for nearly 3 years now. I was able to keep the truck working using the immobilizer fix provided on the first page. But this morning the truck would not start again. I'm thinking I'm ready to just bite the bullet and buy a new fuse and relay box. Is this a difficult process? Where is the best and or quickest place to get the part I need? Can someone direct me to a thread where info is available on replacing the box?

Again, sorry if this is a redundant question. I will be reading this thread throughout the day as time allows.

Thanks for the help.

 

[Scout1982]

I got the famous crank but not start immobilizer problem. I replaced the 20A EFI fuse with a 30A fuse and it started right away. However, it was a temporary fix. I had the same problem again 4 days later. This is what I did to get the engine started. It has been working with no problem for close to 4 weeks now, I thought I would share this with the group.

Fuse terminals: A, B
EFI relay terminals: C, D, E, F

View attachment 1311409

With the EFI fuse in place and relay removed, I ran a wire from the battery positive terminal to terminal F, engine started with no problem. This tells me problem was at upstream or bad relay.

PS: This is a good wire to have in the car for emergency fix.

View attachment 1311410

Factory EFI relay tested good. Next, I shorted terminals E and F, engine cranked but not started. This tells me the power from terminal E was not good enough to start the engine. With the help of voltmeter, I found out there was 0.44V voltage drop between the battery and terminal E with factory 20A fuse in place. Voltage drop was 0.14V with 30A fuse. The engine wouldn't start even with 0.14V voltage drop. I came up with the following to bypass the internal circuit between terminals B & E in order to reduce the voltage drop between the battery and terminal F.

I used a Tyco V23234-A1001-X043 Mini Relay 12V. Make sure the relay you use has suppression protection if you are going to do this, otherwise this could cause damage to your ECM.

Wiring diagram:
Terminal A to 20A inline fuse to terminal 87 of Bosch relay
Terminal F to terminal 30 of Bosch relay
Terminal C to terminal 85 of Bosch relay
Terminal D to terminal 86 of Bosch relay
No connection for terminals B and E

Factory EFI relay can be used in this setup. I used Bosch relay because I want the relay to sit flat in the fuse box. I also put a piece of high density foam between the fuse box cover and Bosch relay to "secure" it better in place.

View attachment 1311417
View attachment 1311418

 

[70 FJ40]

Thanks for the response @Scout1982 This is the fix I was talking about that I have used for the last 2 years but as if this morning. It is no longer working. So I'm trying to figure out where to go from here. I've reread through most of the thread here. And still not quite sure.

 

[lexs470]

Thanks for the response @Scout1982 This is the fix I was talking about that I have used for the last 2 years but as if this morning. It is no longer working. So I'm trying to figure out where to go from here. I've reread through most of the thread here. And still not quite sure.

Didn you try to jump a canle connection directly from the battery. Does that still work ?

 

[lexs470]

Didn you try to jump a canle connection directly from the battery. Does that still work ?

Jumping a cable from battery positive terminal to the f terminal of where the factory relay sits. As per the pics in tnt original thread fix post.

 

[70 FJ40]

I'm away from the truck for the day but when I get back home this evening, I think I will start back at the beginning with the diagnoses if this issue and make sure it's the same problem.

 

[70 FJ40]

@medtro can I get one of your kids? What are you charging? I made my own using the factory relay and it worked for nearly to years but no longer.

 

[70 FJ40]

Sorry not "kids". Kits. I would like to know if I can get one if your kits.
Stinking auto correct.

 

[medtro]

I figured I'd someone else stumbles upon other posts they would get the solution too. Thanks again. You're awesome !

Did you fix your P1600 problem? It might be a good idea to report back so that other who stumbles upon this thread would get the solution.

 

[lexs470]

Yes, once the p1600 code is fixed thanks again to your advice.

 

[medtro]

Thanks for the response @Scout1982 This is the fix I was talking about that I have used for the last 2 years but as if this morning. It is no longer working. So I'm trying to figure out where to go from here. I've reread through most of the thread here. And still not quite sure.

Try power your relay from battery, or do the battery 12v to terminal F test. I am guessing you have bad connection at terminal A.

 

[medtro]

@medtro can I get one of your kids? What are you charging? I made my own using the factory relay and it worked for nearly to years but no longer.

I sent you PM.

 

[70 FJ40]

Ok. Back home and finally have a few minutes to work on the truck. How lucky am I that the driveway is where it decided not to start?! Anyway. I have 12.14 volts at the battery, 12.10 volts at terminal A but only 11.9 volts at terminal F.

 

[70 FJ40]

So I'm wondering if instead of using a kit and new relay why can't I do what @kevin2i did in post #83? Seems like a simpler way to achieve the same thing. I'm not trying to be a jerk or anything. I'm beyond thankful for the knowledge and help on this topic I've received. Just honestly trying to figure out the best thing to get my truck to be reliable.

 

[medtro]

It will depend on where your problem is. If your problem is on the left side of the wire, then it will work fine. If your problem is on the right side of the wire, then you will still have the same problem.

 

[70 FJ40]

Ah yes. That makes sense.

 

[trdcorolla]

Ok. Back home and finally have a few minutes to work on the truck. How lucky am I that the driveway is where it decided not to start?! Anyway. I have 12.14 volts at the battery, 12.10 volts at terminal A but only 11.9 volts at terminal F.

12.1 means your battery is at 50% charge. That may be enough to start your car IF the battery's CCA's aren't too low. Can you test your battery?

 

[70 FJ40]

Ya. Good point. That croosed my mind yesterday. I'm not terribly worried about that though because once I got a chance to work on it last night the truck started just fine with the jumpyer wire and again once hooked back up to my homemade kit. Not sure what he problem was yesterday morning. Thinking maybe one of the wires had just worked loose. It's a pretty frustrating issue.