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SteveO · 11-30-2007, 07:48 AM

Well, I finally got it done. I have fixed the Speedometer problem, and the 4wd EDU problem

Speedometer issue, taken from my website:

Well, it's been a long time coming, but I finally got my speedometer working correctly. After many trails, and mis-information from other sites, its finally working. Let me first say that not all '99 4Runners are the same, and there are many differences between models. The following information pertains to the '99 4Runner Limited, which is particulary difficult to get working due to the multimatic transfer case and ABS speed sensors. So, don't think this info is going to solve your '99 SR5 4Runner woes, I would look at it as more of a guideline, then the actual solution. That said, lets get into it.

Some time ago, I had purchased the SuperLift TruSpeed. I must confess, this was the biggest waist of money I have ever spent. The directions were incorrect and the unit never worked as claimed by the manufacturer. In fact, upon calling the manufacturer about this, their response was less than helpful, actually it was darn right lame. Now, this doesn't mean it won't work for you, I'm just relaying my experience with this waste of a product.

So, in the meantime, I used my GPS as my speedometer. With 3 trips to Moab, 1 trip to Arizona and a few to Farmington, I figure I'm at most 3500 miles off of what my current odometer states.

Ok, on to the real issue. The '99 4Runner Limited uses the ABS sensors at each wheel as speed sensors. The method of the madness is;

The ABS sensors feed the ABS computer - The ABS computer then sends a single speed signel to the Speedometer in the Combination Meter - from there it goes to the ECU. Yes, its a long route, but apparently it works.

Lets start off by taking a look at this picture of the ABS computer and the speed sensors that are attached to the computer. Click on the picture below to open it in a different window.

When looking at this picture, notice the 4 speed sensors, one for each wheel. They are essentially Hall-effect sensors that generate a voltage signal when a piece of steel is move across the face of the sensor. So, this is the root of the issue. When Folks perform a SAS (SAC) the front sensors are removed. This action alone will not stop the speedometer from working, but will bring the ABS light on. In cases such as mine, when folks perform a Full Floater setup for the rear axle, again, the sensors are removed. Thus, without speed sensors, you have no speedometer.

There are some out there who are trying to sell VSS (Vehicle Speed Sensor) units that will attach to a mechanical speed sensor and create a voltage signal. Let me tell you first hand, be careful of what is told to you. Do you own research. I was told by a person of a reputable company some bad information that cost me fifty dollars. After doing the research myself, I figured it out and obtained the correct parts. These gear driven speed sensors do not span a wide range of transfer cases as was stated to me. I would say the company makes some inotative off-road products, but doesn't know too much about speed sensors, as they would imply. Just be careful.

OK, back to the picture. Here you see the speed sensors and you can also see the wire that goes to the ABS light. So, instead of pulling the instrument panel to get to the ABS bulb, just clip the Black wire with Light Blue stripe. This wire comes out of Port 25B on the ABS computer.

This picture is the previous page to the above picture. Notice that if you clip the Black wire with the Light Blue strip, it goes the the ABS light in the combination meter. it also goes to the ABS relay, if you have one. In my case I didn't have a relay, so no worries there.

Also note in this picture that connector 14 on the ABS ECU connects to the Speedometer in the Combination Meter. This Gray wire with Light Blue strip goes directly to the speedometer. What does this mean? Again, you don't have to pull your instrument cluster apart to get to this wire. After hooking up my Tacoma speedometer, I ran the signal wire up through the transfer case boot, underneath the carpet directly to the ABS ECU. I clipped the wire coming out of the ABS ECU and patched my speed signal wire directly into the wire leading to the Speedometer in the combination meter.

Here is a picture of the Combination meter, (pin 1D) receives the speed sensor signal from the ABS ECU, or the VSS, depending on your type of rig. Note the GR-L wire has a note indicating number 1 next to it. This means "5VZ-FE". Also note that the same pin, 1D has an alternate number, 2, going to the VSS. This number two means 3RZ-FE. As well, the 9D pin has the Pink wire going to the VSS for the 3RZ-FE engine style rigs. I assume that when the Combination meter gets power, it powers the VSS, and receives a speed signal back from it via pin 1D. In the case of 4Runners that had ABS as speed sensors, the A17 ABS ECU would apply. Tap into this line to send the signal to the Combination Meter.

Pretty simple right, well....not so fast. One thing you really need to do is get enough voltage to the speed sensor to send a strong signal to the speedometer. My first attempt at this was to hook the hot wire of the speed sensor to a fuse. Not enough voltage. So, you need a good voltage source and a good ground. As noted below, I used the cigerette lighter relay to power my VSS.

I was able to find this picture on the internet and resize it to show what the '98 Tacoma VSS looks like. The VSS I pulled came from a '98 Tacoma with a V6, automatic transmission and chain drive transfer case. I picked up the whole thing for seventy-five dollars, which is a pretty good deal compared to the dealerships asking price of $225. Be sure you get the plug when you get the VSS. You're gonna need the plug with the wires. You may also consider testing the unit before you leave the junk yard. Take a coulpe of alligator clips and a voltage meter. Follow the wire settings below, turn the gear by hand and see if you get a voltage drop from 12v to 0 volts, and it repeats with more turns.

This unit has 3 wires:

Pink, Light Blue and Green with Red stripe.

Pink goes to power, a good 12 volt source. I have heard of people wiring these directly to a hot power source, but I felt this not a good idea. Who knows what could happen if the wires get too hot. What I really needed was a relay to turn the power on and off with the ignition. I hooked the hot wire directly to the Cigerette lighter relay in the engine bay. When the 4Runner is on, and running, it has power. When its off, it no longer has power. Now for those how have shorted out the relay to always have power, this isn't gonna work for ya. But, in my humble opinion, a relay is the best way to power this unit.

The Light Blue wire goes to a good ground. I was able to route this wire up through the transfer case boot to a ground source in the center counsol. Works like a charm.

The Green with Red stripe wire is your signal wire. This wire will connect directly to the Gray wire with Light Blue stripe.

Now to test it. put the rear of the 4Runner on jack stands, put it in gear and see if the speedometer moves. If so, your in business. Of course, with tire changes, it probably will not read correctly.

Dakota Digital makes a really great product that will modify your speed signal and give the speedometer the correct signal.

I was able to pick up one of these units for $80 bucks off ebay. They have great instructions and work very well. One thing I wish they had was a dual switch that would allow me to switch between two different settings, such as for 37" and 35" tires. That wold be cool.

So, there you go, this is how you can get a working speedometer after removing ABS sensors from your rig. Now, I remind you, this was done on a '99 4Runner Limited. Does this mean that all colored wires are the same for your rig? No. I would use this information as more of a guide than step by step factual instructions for your rig. As well, just because I have stated that this is working for me, doesn't mean it will work for you. I don't know wha the electrical issues are on your rig. You may end up trying this and shorting out your Combination Meter. Take responsibility for your actions and research what you are doing before you do it.

PLEASE ABIDE BY THE RULES AND DO NOT POST IN THIS THREAD

11-30-2007, 07:48 AM	#4 (permalink)
SteveO Contributing Member Join Date: Oct 2002 Location: NM Posts: 1,848	3rd Gen ABS Removal and Speedometer fix Well, I finally got it done. I have fixed the Speedometer problem, and the 4wd EDU problem Speedometer issue, taken from my website: Well, it's been a long time coming, but I finally got my speedometer working correctly. After many trails, and mis-information from other sites, its finally working. Let me first say that not all '99 4Runners are the same, and there are many differences between models. The following information pertains to the '99 4Runner Limited, which is particulary difficult to get working due to the multimatic transfer case and ABS speed sensors. So, don't think this info is going to solve your '99 SR5 4Runner woes, I would look at it as more of a guideline, then the actual solution. That said, lets get into it. Some time ago, I had purchased the SuperLift TruSpeed. I must confess, this was the biggest waist of money I have ever spent. The directions were incorrect and the unit never worked as claimed by the manufacturer. In fact, upon calling the manufacturer about this, their response was less than helpful, actually it was darn right lame. Now, this doesn't mean it won't work for you, I'm just relaying my experience with this waste of a product. So, in the meantime, I used my GPS as my speedometer. With 3 trips to Moab, 1 trip to Arizona and a few to Farmington, I figure I'm at most 3500 miles off of what my current odometer states. Ok, on to the real issue. The '99 4Runner Limited uses the ABS sensors at each wheel as speed sensors. The method of the madness is; The ABS sensors feed the ABS computer - The ABS computer then sends a single speed signel to the Speedometer in the Combination Meter - from there it goes to the ECU. Yes, its a long route, but apparently it works. Lets start off by taking a look at this picture of the ABS computer and the speed sensors that are attached to the computer. Click on the picture below to open it in a different window. When looking at this picture, notice the 4 speed sensors, one for each wheel. They are essentially Hall-effect sensors that generate a voltage signal when a piece of steel is move across the face of the sensor. So, this is the root of the issue. When Folks perform a SAS (SAC) the front sensors are removed. This action alone will not stop the speedometer from working, but will bring the ABS light on. In cases such as mine, when folks perform a Full Floater setup for the rear axle, again, the sensors are removed. Thus, without speed sensors, you have no speedometer. There are some out there who are trying to sell VSS (Vehicle Speed Sensor) units that will attach to a mechanical speed sensor and create a voltage signal. Let me tell you first hand, be careful of what is told to you. Do you own research. I was told by a person of a reputable company some bad information that cost me fifty dollars. After doing the research myself, I figured it out and obtained the correct parts. These gear driven speed sensors do not span a wide range of transfer cases as was stated to me. I would say the company makes some inotative off-road products, but doesn't know too much about speed sensors, as they would imply. Just be careful. OK, back to the picture. Here you see the speed sensors and you can also see the wire that goes to the ABS light. So, instead of pulling the instrument panel to get to the ABS bulb, just clip the Black wire with Light Blue stripe. This wire comes out of Port 25B on the ABS computer. This picture is the previous page to the above picture. Notice that if you clip the Black wire with the Light Blue strip, it goes the the ABS light in the combination meter. it also goes to the ABS relay, if you have one. In my case I didn't have a relay, so no worries there. Also note in this picture that connector 14 on the ABS ECU connects to the Speedometer in the Combination Meter. This Gray wire with Light Blue strip goes directly to the speedometer. What does this mean? Again, you don't have to pull your instrument cluster apart to get to this wire. After hooking up my Tacoma speedometer, I ran the signal wire up through the transfer case boot, underneath the carpet directly to the ABS ECU. I clipped the wire coming out of the ABS ECU and patched my speed signal wire directly into the wire leading to the Speedometer in the combination meter. Here is a picture of the Combination meter, (pin 1D) receives the speed sensor signal from the ABS ECU, or the VSS, depending on your type of rig. Note the GR-L wire has a note indicating number 1 next to it. This means "5VZ-FE". Also note that the same pin, 1D has an alternate number, 2, going to the VSS. This number two means 3RZ-FE. As well, the 9D pin has the Pink wire going to the VSS for the 3RZ-FE engine style rigs. I assume that when the Combination meter gets power, it powers the VSS, and receives a speed signal back from it via pin 1D. In the case of 4Runners that had ABS as speed sensors, the A17 ABS ECU would apply. Tap into this line to send the signal to the Combination Meter. Pretty simple right, well....not so fast. One thing you really need to do is get enough voltage to the speed sensor to send a strong signal to the speedometer. My first attempt at this was to hook the hot wire of the speed sensor to a fuse. Not enough voltage. So, you need a good voltage source and a good ground. As noted below, I used the cigerette lighter relay to power my VSS. I was able to find this picture on the internet and resize it to show what the '98 Tacoma VSS looks like. The VSS I pulled came from a '98 Tacoma with a V6, automatic transmission and chain drive transfer case. I picked up the whole thing for seventy-five dollars, which is a pretty good deal compared to the dealerships asking price of $225. Be sure you get the plug when you get the VSS. You're gonna need the plug with the wires. You may also consider testing the unit before you leave the junk yard. Take a coulpe of alligator clips and a voltage meter. Follow the wire settings below, turn the gear by hand and see if you get a voltage drop from 12v to 0 volts, and it repeats with more turns. This unit has 3 wires: Pink, Light Blue and Green with Red stripe. Pink goes to power, a good 12 volt source. I have heard of people wiring these directly to a hot power source, but I felt this not a good idea. Who knows what could happen if the wires get too hot. What I really needed was a relay to turn the power on and off with the ignition. I hooked the hot wire directly to the Cigerette lighter relay in the engine bay. When the 4Runner is on, and running, it has power. When its off, it no longer has power. Now for those how have shorted out the relay to always have power, this isn't gonna work for ya. But, in my humble opinion, a relay is the best way to power this unit. The Light Blue wire goes to a good ground. I was able to route this wire up through the transfer case boot to a ground source in the center counsol. Works like a charm. The Green with Red stripe wire is your signal wire. This wire will connect directly to the Gray wire with Light Blue stripe. Now to test it. put the rear of the 4Runner on jack stands, put it in gear and see if the speedometer moves. If so, your in business. Of course, with tire changes, it probably will not read correctly. Dakota Digital makes a really great product that will modify your speed signal and give the speedometer the correct signal. I was able to pick up one of these units for $80 bucks off ebay. They have great instructions and work very well. One thing I wish they had was a dual switch that would allow me to switch between two different settings, such as for 37" and 35" tires. That wold be cool. So, there you go, this is how you can get a working speedometer after removing ABS sensors from your rig. Now, I remind you, this was done on a '99 4Runner Limited. Does this mean that all colored wires are the same for your rig? No. I would use this information as more of a guide than step by step factual instructions for your rig. As well, just because I have stated that this is working for me, doesn't mean it will work for you. I don't know wha the electrical issues are on your rig. You may end up trying this and shorting out your Combination Meter. Take responsibility for your actions and research what you are doing before you do it. PLEASE ABIDE BY THE RULES AND DO NOT POST IN THIS THREAD __________________ http://www.Hunt4Steve.com In the span of time, life is short. Our life is like a wave on the ocean, a flower in the field, here today and gone tomorrow. Know yourself, know where you will spend eternity, for NOTHING else will matter when you die. Last edited by SteveO; 11-30-2007 at 08:56 AM.