fix for immobilizer issue? (3 Viewers)

[BOB F]

Here is what I have found with issues I have had myself, hope this helps.

#1. If the vehicle turns over but does not start it is most likely the imobalizer or EFI fuse. (Replaced my fuse even though it looked good and no more issue.)

#2. If vehicle does not turn over and just clicks and the battery is good it is most likely the starter.
Most of the time the starter will start giving you warnings before it goes out completely. If you have had these symptoms and the battery is good it's time to replace the starter or starter contacts.

#3. Bad battery.
This will have similar symptoms as above but the vehicle will not start without a jump or charge.

These are 3 most common issues with the 100 series and I have had all 3 issues with mine. Hope this helps.

That is a good synopsis but as for #2 in my case I had incidents within one week of each other of no crank , resolved immediately by throwing a jump charge on (happened twice) followed by a crank no start episode, resolved by changing efi fuse to 30amp.

As of this writing all is well. This truck got a new starter maybe 6-7 years ago.

We shall see

 

[benc]

That is a good synopsis but as for #2 in my case I had incidents within one week of each other of no crank , resolved immediately by throwing a jump charge on (happened twice) followed by a crank no start episode, resolved by changing efi fuse to 30amp.

As of this writing all is well. This truck got a new starter maybe 6-7 years ago.

We shall see

So a low or week battery? A week battery can cause a week starter to act up as well, through a jumper on and it gives the starter that little extra it needs.
Still, most of the time on these vehicles if there is nothing or just a click it is the starter, battery or connections, the imobalizer or EFI fuse issue will allow the vehicle to crank but not start.

 

[BOB F]

I left out that I replaced the battery after it required a jump to start and then the next day it would crank , no start.

Changed the fuse to 30amp and so far so good. I'll update this thread if it goes south again

 

[toyotatruckjunkie]

I have had a paper clip in place for over a month now w/o ANY issues, but I couldn't leave it that way. I came up with a slightly better solution that seems to work at the moment. I'm really not horribly proud of this solution, but at least now it has a fuse funciton to it to provide some sort of protection for the circuit.

I used a large paper clip (with larger diameter wire to make better contact), (2) blade connectors, and a larger style 20A fuse. Not really rocket science. I am still trying to Insert/Attach/Embed a pic with the new format of Mud, but I will report back from time to time on how this solution seems to works.

 

[01Cruiser]

2001 Cruiser, 150k fell victim to the immobilizer issue. I didn't know about this issue the first night the truck wouldn't start. I let it sit while I was at work and a few hours later she started up no issues. A few weeks later she wouldn't start again. This time I was prepared with a new fuse. Swapped the EFI and it started right up. Worked for a day and died again. Fuse box was replaced and no issues since! Funny part of story is that Toyota Dealer INSISTED I needed to replace ECU despite my suggestions. I insisted, and ultimately a head tech arrived at dealer and within minutes diagnosed, and agreed it was the fuse box. Thanks to this board, I saved quite a bit of $$. Thanks everyone!

 

[toyotatruckjunkie]

Well my last fix lasted about a month until it became unreliable. Yesterday my wife had the crank no start issue twice. I am so proud of her that she is not afraid to pop the hood, open the fuse box, wiggle my fused paper clip McGyver fix and get her truck to start, but not a condition I am happy about. (She has impressed the heck out of her girlfriends).
BUT I had to do something else.

I will eventually replace the fuse box but not yet. I took a 20a fuse, added a small "button" of solder to each side of the fuse contact areas. It wouldn't push into the socket so I shaved the solder down into a wedge shape. It took a bit of force to get it into the socket but it is in and tight now. We'll see how long that lasts.

Btw, after the above mentioned modified fuse fix, I took the truck thru a car wash that had a jet coming up from the floor into the engine compartment. While sitting in the car wash the battery light came on briefly and went back off wo any other symptoms.

This was the same as the time I drove it thru deep water and got the battery light briefly. Perhaps enough water is getting sprayed at the bottom of the fuse box to cause some corrosion. Disappointing for a LC but my only likely cause. There was no water inside the fuse box after the car wash. We use that same car wash at least weekly.

Does anyone else have similar results w water being sprayed from below?

 

[timmbuck2]

SO it happened again today...leaving the boys' football games, and it just cranked. I could see the red security icon blinking. I just left the key in and 5 minutes later the icon stopped blinking, and it started right up. Still not sure what the perm fix will be....but good to know the trick still works...

 

[Eicca]

Happened to ours today. Wouldn't fire, just cranked and cranked. No CEL in "on" position. The security light kept blinking. Tried changing fuses and relay and jumping the EFI fuse with a paperclip, no success. After letting it sit in the "on" position for about seven minutes, the immobilizer decided to un-immobilize and I was able to start it up and drive to O'Reilly to get some CRC electrical cleaner. I'm going to try disassembling the whole fuse box and cleaning the contacts as well as cleaning the ECU contacts too.

 

[lwarden]

This happened to my wife's LC this last weekend. Was very glad to find this thread and all the helpful info in it.
Pulled the fuse and tried to clean and increase the spring pressure on the fuse and reassembled with dielectric grease and this lasted for a couple days. Was just about to pull the trigger on a new fuse/relay box and decided that I'd take a shot at getting to the root cause on this and fix it more cost effectively.
I decided to add an external fuse holder as someone else did but without removing the fuse box.

This is what I beleive is root cause for this problem:
There are two brass plated copper tabs coming up which are shown in the previous post where the box was fully assembled. One of these leads to the +12 side and the other goes to the relay to provide the fused power to the EFI. Inside the plastic fuse tower there are two pressed metal spring contact boxes which surround the two tabs coming up and make the interface with the fuse. I believe the connection between these contact boxes and the tabs is where the issue is. When someone takes a fuse in or out it giggles this component and probably makes slightly better contact. When I disassembled the fuse tower and removed the pressed spring contacts the one leading to the EFI relay was discolored and had obviously gotten very hot, likely due to high resistance to the fuse blade. That is the problem. No amount of cleaning will fix this problem and adding jumpers and different fuses will only temporarily patch the situation. Of course you can buy a new fuse box, but it will still probably have the same issue down the road.

The only part you need is an inline fuse holder similar to the one shown earlier in this thread, although I used a mini-fuse holder. I'm sure there are better options than the one I used but that was all they had at my local auto parts store.

Procedure goes as follows:
1. Remove the positive lead from the battery.
2. Use a dremel and small sharp wood chisel to remove the plastic tower portion of the EFI fuse holder. This is where the "smoking gun" to this problem appeared. I didn't do the cleanest job of removing the plastic....

3. I carefully drilled two 3/16" holes towards the front of the two tabs to give some room to get a soldering iron in.
4. I abraded the two tabs on the front surface and cleaned with Acetone and tinned them with solder.

5. I also tinned the fuse holder leads.

 

[lwarden]

Continued from above...

6. Applied a couple pieces of marine grade heat shrink to the fuse holder leads.
7. Soldered the new fuse holder to the tinned tabs, this took some heat...
8. Heat up heat shrink.

9. Job done, car fired right up!

Total time 1 hour, cost, $4.95.

 

[drjman]

Just found this thread. I experienced this issue on vacation in Tahoe, replaced the alternator (bad) in the rental house (lol). Still had intermittent issues. I'm pretty sure it's the immobilizer. Happened again today and told the wife to check the red light if it cranks and doesn't start. I haven't checked the fuse yet. In my process to get it started, I unplugged/plugged the IG1 IG2 and Starter fuses. I think time was on my side and why it finally started, not removing the fuses. Going to keep an eye on the problem. My other thought was maybe my replcement key fob was not functioning properly. we'll see.

 

[drjman]

So the fuse was not blown, but there was some corrosion. I replaced it and it worked for a little while. The issue was still happening and removing the fuse and EFI relay and reseating would get it to start again. Now it won't start at all. I jumped the battery to the EFI relay connector and I was able to get it started. I tested the relay and it is operating normally. I then tested voltage

20amp fuse was about 12.47 (same as battery
ACC trigger (fires off the relay) tested at 11.47 (should this be above 12?)
with the fuse in, there was no drop in voltage to the high amp socket in the relay plug.

I'm thinking that the relay itself isn't getting enough juice to to engage the magnet (once engaged, there is definitely continuity). I lack the good wiring diagrams with my AllDataDIY account and I can't find where that low voltage line is coming from. I know it's only live then the ignition is in the ON position.

I was looking into doing this fix: My immobilizer fix
But he's reusing the trigger line for the relay.

 

[drjman]

I was messing with wiring while plugging in the relay again and felt/heard it engage and realized 11.5v is enough and not the issue. I rigged up my own bypass using the original relay and it started right up.

Thanks to @medtro !!!

My immobilizer fix

 

[highonpottery]

I have been reading up on this - is it actually an immobiliser issue or is it more of a problem with our EFI fuse contacts/fuse block?

Pretty sure my cruiser doesn't have the immobiliser as I have no dash light in the place everyone says they have one next to the stereo.

Anyways, I do see everyone with "immobiliser problems" referring to and resolving the issue with the 20A EFI fuse -- and I DO have What I think is that issue. Last few weeks have experienced 3x crank but no start situations. First two times it started up eventually, the last time it did not and I ended up tinkering with the 20A fuse and it started up. Don't want to have it happen again when wife or my inlaws are driving around the kids.

For those who did the fuse box for $450, did you install it yourself? I wasn't seeing any instructions for doing so - is it literally a plug and play setup where I can just swap plugs and I'm good?

I saw the more invasive approach to opening it up and soldering in an inline fuse holder, seems legit to me if it works and saves $ -- was that the 7hr repair job I read about earlier? Need to back track that.

 

[wildsmith]

I wouldn't replace the fuse box or open it up if I had to do another, I'd copy lwarden for a fix with least new connections added, or like drjman if it has to be a plug in solution / no chopping plastic and soldering.

 

[BOB F]

We suddenly had an immobiliser issue this week and no amount of fiddling with the fuse, jumping it, hitting it etc would make it work even briefly. I can't find any threads with an immobiliser fault where the fuse box isn't implicated so I figured I'd take it apart and see if there was anything to fix in there. It didn't fix our problem but here's what I found in case it helps someone else:

Fusebox with the suspect fuse and relay circled in red

I removed the fusebox from the truck. If you undo the clips holding wires to the casing you can tip the fusebox up enough to get at the connectors underneath and disconnect them. With the fusebox on the bench I removed the bottom cover but I forgot to take a photo of that. That cover is held on by clips around the sides and 2 plastic rivets towards the middle that I had to drill the tops off to release it. Under that cover this is what you've got.

The tracks are laid out on another layer of plastic and lift off. Some of them have male spade connectors that go through to layers underneath and some form the connections for the plugs on the wiring loom. I put the parts in a pile (on the cover I forgot to photo) to get the next layer of plastic off thinking I'd be seeing the back of the fuses!

Turns out there are a few layers, I didn't count but 5 I think:

With all the layers removed the back of the fuse and relay connectors are revealed. They are like double ended connectors pushed into the holes, fuses or relays push into the top side and these tracks push into the underside. The 2 connectors for the EFI fuse circled in red were very loose and barely making contact but no sign of carbon or corrosion.

I didn't feel the connectors were repairable and doubt I'd be able to get replacements so I removed them, drilled out the holes, put the tails of an inline fuse holder through the holes and soldered to the tracks that would go into those holes:

Then I put the rest of it back together. The connectors under the fuse box all only fit in one place.

 

[BOB F]

This is exactly what I had in mind to fix my efi fuse issue. If I look down into my fuse location with the fuse out, the female recepticle on the outboard side which is the 12v supply, is depressed lower than its mate.

I can't figure any way to fix this other than what you did or a new fuse box.

How has the fix and irked and were you able to reassemble it all without issues? I just envision doing that and not bring able to get it back together again

 

[BOB F]

We suddenly had an immobiliser issue this week and no amount of fiddling with the fuse, jumping it, hitting it etc would make it work even briefly. I can't find any threads with an immobiliser fault where the fuse box isn't implicated so I figured I'd take it apart and see if there was anything to fix in there. It didn't fix our problem but here's what I found in case it helps someone else:

Fusebox with the suspect fuse and relay circled in red

I removed the fusebox from the truck. If you undo the clips holding wires to the casing you can tip the fusebox up enough to get at the connectors underneath and disconnect them. With the fusebox on the bench I removed the bottom cover but I forgot to take a photo of that. That cover is held on by clips around the sides and 2 plastic rivets towards the middle that I had to drill the tops off to release it. Under that cover this is what you've got.

The tracks are laid out on another layer of plastic and lift off. Some of them have male spade connectors that go through to layers underneath and some form the connections for the plugs on the wiring loom. I put the parts in a pile (on the cover I forgot to photo) to get the next layer of plastic off thinking I'd be seeing the back of the fuses!

Turns out there are a few layers, I didn't count but 5 I think:

With all the layers removed the back of the fuse and relay connectors are revealed. They are like double ended connectors pushed into the holes, fuses or relays push into the top side and these tracks push into the underside. The 2 connectors for the EFI fuse circled in red were very loose and barely making contact but no sign of carbon or corrosion.

I didn't feel the connectors were repairable and doubt I'd be able to get replacements so I removed them, drilled out the holes, put the tails of an inline fuse holder through the holes and soldered to the tracks that would go into those holes:

Then I put the rest of it back together. The connectors under the fuse box all only fit in one place.

 

[BOB F]

I wouldn't replace the fuse box or open it up if I had to do another, I'd copy lwarden for a fix with least new connections added, or like drjman if it has to be a plug in solution / no chopping plastic and soldering.

I have the box out and am having issues getting the back off. How did you do that? I see the clips on the side and I drilled out the rivets, but I can't get the back to budge.

Thank you

 

[wildsmith]

Pretty sure it was just the rivets and clips but the clips were a bit of a fiddle to get them to release.