car wont crank unless jumped, battery dying, low idling ( sometimes at 100 rpms) and then stalling, driving at 50mph and throttling and drops to 0mph

[cruisingalong45]

I have this long list of hopefully closely correlated problems as they all showed up at once. (background info) I just bought this 1994 land cruiser (I'm 19) so still new to this world especially the land cruiser world... anyways, I was getting ready to leave one day and car would not turn over at all and I discovered that is was do to an aftermarket alarm that I eventually flipped the switch to and the car started, but only with a jump. it idled very low and and I had to make it home most of the way in neutral idling very high so the car didn't stall. as I was driving home a few things happened, 1- I would be driving and the gauges for the rpm and mph would shoot up and down. that then stopped and they sat at the correct levels and when I throttled they both shot to 0. and then they both sat at 0 for the rest of the way home, while I was driving the battery level was going down and I barely made it home before it died. been sitting in my driveway where I messed with the alarm system, the battery, and the fusible link. so having said that, are these common problems together? and has anyone got any advice?

 

[jonheld]

I have this long list of hopefully closely correlated problems as they all showed up at once. (background info) I just bought this 1994 land cruiser (I'm 19) so still new to this world especially the land cruiser world... anyways, I was getting ready to leave one day and car would not turn over at all and I discovered that is was do to an aftermarket alarm that I eventually flipped the switch to and the car started, but only with a jump. it idled very low and and I had to make it home most of the way in neutral idling very high so the car didn't stall. as I was driving home a few things happened, 1- I would be driving and the gauges for the rpm and mph would shoot up and down. that then stopped and they sat at the correct levels and when I throttled they both shot to 0. and then they both sat at 0 for the rest of the way home, while I was driving the battery level was going down and I barely made it home before it died. been sitting in my driveway where I messed with the alarm system, the battery, and the fusible link. so having said that, are these common problems together? and has anyone got any advice?

If you have a standard flooded cell battery, it's done. Once it is discharged, it likely won't take a full charge anymore.
All of the issues you stated are related to a failing power source.
I would replace the battery and fusible links as a first step (90982-08264 available from any dealer)

Make sure the battery terminals are tight.
Have your alternator tested, as you've put a heavy load on it running with a depleted battery.

 

[cruisingalong45]

If you have a standard flooded cell battery, it's done. Once it is discharged, it likely won't take a full charge anymore.
All of the issues you stated are related to a failing power source.
I would replace the battery and fusible links as a first step (90982-08264 available from any dealer)
View attachment 4140008
Make sure the battery terminals are tight.
Have your alternator tested, as you've put a heavy load on it running with a depleted battery.

I had my multi meter with the negative on the negative terminal and the positive on the alternator and it was reading 6 volts. Going to buy new terminals and fusible links. I also couldn't test to see if the links are corroded because the fusible links as I couldn't get the socket off. But when you say the battery wont take a full charge because its discharged do you just mean when a battery dies? also maybe the alarm system has something to do with it is as the seller said it had some type of electrical problems, I don't want to misdiagnose but just something else I need to consider.

 

[jonheld]

I had my multi meter with the negative on the negative terminal and the positive on the alternator and it was reading 6 volts. Going to buy new terminals and fusible links. I also couldn't test to see if the links are corroded because the fusible links as I couldn't get the socket off. But when you say the battery wont take a full charge because its discharged do you just mean when a battery dies? also maybe the alarm system has something to do with it is as the seller said it had some type of electrical problems, I don't want to misdiagnose but just something else I need to consider.

First thing you need to do is get the battery/charging system together.
Flooded cell batteries once discharged below a certain voltage will not come back. Replace the battery.
Checking system voltage with a possibly faulty battery is pointless because a shorted battery cell will drag system voltage down. Replace the battery.

Fusible links are basically sections of wire covered with a flameproof silicone jacket. The wire is designed to melt beyond a certain current draw. The jacket protects from flame.
You can't test fusible links with your eyeballs and they can fracture internally due to vibration over the years and become intermittent. They run about $12-16 for the set of 3. Replace them. Buy 2 sets and keep 1 in the glovebox for a spare.

Not sure what you mean by "couldn't get the socket off". What "socket" are you referring to?

 

[mesa man]

^^^ after replacing battery and testing and possibly replacing alternator, remove all crappy aftermarket wiring from said alarm to get back to factory condition. A simple test light will help you isolate power interruptions in battery cables. Clean ALL connections and tighten, Get a FSM (factory service manual) and baseline your rig.
We love our 94 FZJ80 after dialing it in.
Good luck

 

[mesa man]

the alarm system has something to do with it is as the seller said it had some type of electrical problems,

^^^This is the problem! Remove and repair ASAP!

 

[cruisingalong45]

First thing you need to do is get the battery/charging system together.
Flooded cell batteries once discharged below a certain voltage will not come back. Replace the battery.
Checking system voltage with a possibly faulty battery is pointless because a shorted battery cell will drag system voltage down. Replace the battery.

Fusible links are basically sections of wire covered with a flameproof silicone jacket. The wire is designed to melt beyond a certain current draw. The jacket protects from flame.
You can't test fusible links with your eyeballs and they can fracture internally due to vibration over the years and become intermittent. They run about $12-16 for the set of 3. Replace them. Buy 2 sets and keep 1 in the glovebox for a spare.

Not sure what you mean by "couldn't get the socket off". What "socket" are you referring to?

The nut holding the links on ( not socket ) I'm going to fully charge the battery to see if the red discharge light on the dash goes away before I buy a new battery. but any videos or advice on removing the alarm system?

 

[Kernal]

IME a handy tool to loosen the nuts on the AM1 Junction box is a impact driver, zzzippp and done. I use a M12 impact driver for almost every job
on my 80 when working on bolts up to ~12-14mm; it's quicker and smaller compared to a cordless ratchet, just add a 1/4" hex socket adapter. Main advantage over a compact cordless impact wrench is that it's lighter. It's also got a screw start mode ie: slow speed low torque if needed.

Example:

https://www.homedepot.com/p/Milwaukee-M12-FUEL-12V-Lithium-Ion-Brushless-Cordless-1-4-in-Hex-Impact-Driver-Kit-w-Two-2-0Ah-Batteries-Charger-Soft-Case-3453-22/321180376

 

[mudgudgeon]

I'm going to fully charge the battery to see if the red discharge light on the dash goes away before I buy a new battery.

I agree with above, sounds like the battery is toast.

If you charge it, test it under load. A battery with a bad cell can show 12volts of charge, but put a load on it, that voltage can drop immediately.
Good way to test is read the multi meter while starting the engine. Starter motor will pull enough load to show the true voltage. A good battery will still show 12volts + while the starter is running.

 

[cruisingalong45]

I agree with above, sounds like the battery is toast.

If you charge it, test it under load. A battery with a bad cell can show 12volts of charge, but put a load on it, that voltage can drop immediately.
Good way to test is read the multi meter while starting the engine. Starter motor will pull enough load to show the true voltage. A good battery will still show 12volts + while the starter is running.

yea mine dropped instantly by atleast 4 volts and then started counting down as it ran.

 

[Old Nick]

Welcome. You've bought the best year of the 80 series... (but, I'm a little biased).

As others have mentioned:
1) New battery
2) New Fusible Link (is the check engine light illuminating as you try to start your truck? If it isn't, your link is toast). As others have said, it's a cheap part and essential. By 2 new ones. Install the first and put the other in your glovebox.
3) Pull the alarm system. The "factory" alarm on our 80 was malfunctioning and it absolutely messed with proper starting of the vehicle. After I pulled it, those things resolved immediately.

If I were you, I would pull the alarm before installing the new battery and fusible link.

But, there were a few other things that needed replacing to get our rig starting and running correctly. Well, actually, there were a ton of other things... lol... but I would suggest the following:

You'll also want to check your throttle position sensor (TPS)
AND, your air idle control valve (AICV). Toyota no longer makes the '94 and earlier unit, but the '95 and after one fits and works just fine. There after aftermarket versions for the '94, but they are STUPID expensive.
Lastly, check your EFI relay... it's in the engine bay in fuse box/bank near the battery. I would go ahead and replace it. Again, buy two and keep the extra in your glovebox.

Lastly, open up your air filter. Either give it a good cleaning or buy a new one.

Then, start searching for "baselining" threads in this forum. You'll find lots of excellent advice about what to tackle to get your truck running tip-top.

 

[mudgudgeon]

yea mine dropped instantly by atleast 4 volts and then started counting down as it ran.

It's cooked

 

[MissahPapaJ]

Battery issues can cause a myriad of nearly unexplainable issues especially when poor connections or discharged / bad cells are part of that equation. Take all the advice aforementioned above you’ll be pooping in tall cotton in no time. Rid yourself of the alarm system, they’re all different but the some what the same find a box it’s usually under the drivers side kick panel around ( above ) the brake and accel pedal somewhere depending on how it was deemed fit to install, it will stick out like a sore thumb ( non factory wire colors ) remove all wiring and properly repair any splices etc. don’t skimp.. pimp!

 

[cruisingalong45]

Welcome. You've bought the best year of the 80 series... (but, I'm a little biased).

As others have mentioned:
1) New battery
2) New Fusible Link (is the check engine light illuminating as you try to start your truck? If it isn't, your link is toast). As others have said, it's a cheap part and essential. By 2 new ones. Install the first and put the other in your glovebox.
3) Pull the alarm system. The "factory" alarm on our 80 was malfunctioning and it absolutely messed with proper starting of the vehicle. After I pulled it, those things resolved immediately.

If I were you, I would pull the alarm before installing the new battery and fusible link.

But, there were a few other things that needed replacing to get our rig starting and running correctly. Well, actually, there were a ton of other things... lol... but I would suggest the following:

You'll also want to check your throttle position sensor (TPS)
AND, your air idle control valve (AICV). Toyota no longer makes the '94 and earlier unit, but the '95 and after one fits and works just fine. There after aftermarket versions for the '94, but they are STUPID expensive.
Lastly, check your EFI relay... it's in the engine bay in fuse box/bank near the battery. I would go ahead and replace it. Again, buy two and keep the extra in your glovebox.

Lastly, open up your air filter. Either give it a good cleaning or buy a new one.

Then, start searching for "baselining" threads in this forum. You'll find lots of excellent advice about what to tackle to get your truck running tip-top.

the check engine light does show up so I'm not sure its the root of my problems. I disconnected the alarm and it doesn't go off anymore. ordering new fusible links today.

 

[Old Nick]

the check engine light does show up so I'm not sure its the root of my problems. I disconnected the alarm and it doesn't go off anymore. ordering new fusible links today.

Just want to clarify. When you disconnected the alarm, the alarm itself has stopped working, or the check engine light comes on and stays on? Sorry to be a dolt.

If your check engine light illuminates, it means that your fusible link is probably functioning as it should, but even so, if it hasn't been changed out in who knows when, doing that now is the safe option.

And as @MissahPapaJ suggested above, I wouldn't just disconnect that alarm, I'd get the entire peace of junk removed from your truck.

 

[Old Nick]

Here's the mess that I pulled out of our rig...

Where is the "brain" for your alarm located? Just start at that point and then work your way to all of the connectors. If it connects to factory points along its run, be sure to reconnect factory to factory connections. If you don't do that, you'll get nothing upon trying to start your rig... don't ask me how I discovered that... lol.

 

[cruisingalong45]

Here's the mess that I pulled out of our rig...

Where is the "brain" for your alarm located? Just start at that point and then work your way to all of the connectors. If it connects to factory points along its run, be sure to reconnect factory to factory connections. If you don't do that, you'll get nothing upon trying to start your rig... don't ask me how I discovered that... lol.

View attachment 4141466

View attachment 4141465

I don't really know what I'm looking at and what's what

 

[Old Nick]

View attachment 4141616


View attachment 4141617
View attachment 4141615

I don't really know what I'm looking at and what's what

Gosh, man, that’s rough. There used to be several factory connectors in that last picture. They all appear to be gone. If there is some slack in the wiring, give it a little tug just to see if the factory connectors are still in the pillar. That mess is beyond my skills without being there with you. I’m going to tag @Malleus at @Broski on this one. Also @BILT4ME and @TYM4FUN . Gents, what do you think?

What is the brand of the aftermarket system?

 

[Malleus]

Looks like the standard "professional" alarm/stereo installation practice. Rip it all out.

Cover all the wounds from the vampire taps with heat shrink...and garlic.

 

[Malleus]

the check engine light does show up so I'm not sure its the root of my problems. I disconnected the alarm and it doesn't go off anymore. ordering new fusible links today.

No check engine light doesn't necessarily mean no power; lots of geniuses remove the bulb. Test your fusible link – with a meter. A spare is good practice.