ABS/VSC/TRAC light on - speedometer not working - Techstream won't connect (1 Viewer)

[bmorgan]

Full disclosure: I'm an 80 series guy. But when your small town knows you are a Land Cruiser guy, you get all of them. So please excuse my lack of knowledge of the 200 series. Good to see Onur is still in the LC world!

A friend brought over their 2011 LC200 with a little over 200k miles. The brake light is on, the ABS/VSC/TRAC light is on, and the speedometer isn't working. I connected my Techstream. It connected to the car and I was able to connect to several different systems, but not the ABS/VSC/TRAC system. Of those systems checked, it was the only system that didn't connect.

I tried the easy stuff. I disconnected the battery for a bit. I tried to perform the accelerator 3X thing - not sure if it did anything. I've been reading as much as I can, but I'm running out of runway. I've read that each wheel has a speed sensor, but since I cannot even connect to the ECU, I'm leaning towards the ECU itself. Does anyone has any guidance or ways I can verify the culprit? I started with the FAQ section but didn't see anything there. I also did a general search in MUD, but all I've found were 100 series references.

Thank you!

 

[Ratchey]

Is the 4WD light on? I ask because we have had 2 trips (towing both times long distance) where that series of lights were on including the 4WD light and the RPM and speedo would just drop to 0, come back on for a few sec, drop again, come back on then drop for about 5 min. I was unable to shift into 4lo during that period. Both times it cleared on its own after about 10 min. I didn't have my laptop so couldn't connect to Techstream anyway.

 

[Sandroad]

Full disclosure: I'm an 80 series guy. But when your small town knows you are a Land Cruiser guy, you get all of them. So please excuse my lack of knowledge of the 200 series. Good to see Onur is still in the LC world!

A friend brought over their 2011 LC200 with a little over 200k miles. The brake light is on, the ABS/VSC/TRAC light is on, and the speedometer isn't working. I connected my Techstream. It connected to the car and I was able to connect to several different systems, but not the ABS/VSC/TRAC system. Of those systems checked, it was the only system that didn't connect.

I tried the easy stuff. I disconnected the battery for a bit. I tried to perform the accelerator 3X thing - not sure if it did anything. I've been reading as much as I can, but I'm running out of runway. I've read that each wheel has a speed sensor, but since I cannot even connect to the ECU, I'm leaning towards the ECU itself. Does anyone has any guidance or ways I can verify the culprit? I started with the FAQ section but didn't see anything there. I also did a general search in MUD, but all I've found were 100 series references.

Thank you!

One thing that may help is to use google for mud searches and use 200 Land Cruiser ih8mud along with the problem in the search line.

It may be the ecu, but it could also be corroded electrical connections leading to/from the ecu. There is a history of water in the door sills or behind the dash from clogged sunroof drains or leaking windshields causing corroded connectors leading to odd dash lights and electrical gremlins. Before replacing parts, check for water or evidence of water inside. There are long threads on that.

 

[tbisaacs]

Would also rule out the obvious and visually inspect front wheel speed sensors and listen for noise from rear bearings or for gear oil seeping out the rear hubs. These sensors can cause all kinds of VSC issues when bad.

 

[bmorgan]

One thing that may help is to use google for mud searches and use 200 Land Cruiser ih8mud along with the problem in the search line.

It may be the ecu, but it could also be corroded electrical connections leading to/from the ecu. There is a history of water in the door sills or behind the dash from clogged sunroof drains or leaking windshields causing corroded connectors leading to odd dash lights and electrical gremlins. Before replacing parts, check for water or evidence of water inside. There are long threads

One thing that may help is to use google for mud searches and use 200 Land Cruiser ih8mud along with the problem in the search line.

It may be the ecu, but it could also be corroded electrical connections leading to/from the ecu. There is a history of water in the door sills or behind the dash from clogged sunroof drains or leaking windshields causing corroded connectors leading to odd dash lights and electrical gremlins. Before replacing parts, check for water or evidence of water inside. There are long threads on that.

Been on this forum for 20 years. I looked extensively before posting. I promise. I read about the door sill leaks. I also read about the speed sensors. I have not read about the bearings leaking until now.

One thing that may help is to use google for mud searches and use 200 Land Cruiser ih8mud along with the problem in the search line.

It may be the ecu, but it could also be corroded electrical connections leading to/from the ecu. There is a history of water in the door sills or behind the dash from clogged sunroof drains or leaking windshields causing corroded connectors leading to odd dash lights and electrical gremlins. Before replacing parts, check for water or evidence of water inside. There are long threads on that.

 

[Boston Mangler]

Had similiar, very time consuming to diagnose issue on my 2014 Tundra

Lonnnnnng story short, one of the connectors to the rear wheel speed sensor got broken off.

Was weird because it wasnt throwing any codes, and everything seemed fine, but dash was a christmas tree

The rear wiring harness for the ABS is in a REALLLY stupid position on both the Tundra and the 200

Stick your head under there and take a look and check the connections

 

[bmorgan]

Thanks guys. I can assure you I did extensive reading on the subject. I've been on mud for 20 years and far enough along to have my own Techstream setup. I wouldn't dare come on here until I've done some leg work first. I read about some of these items, but I wanted to hear from the guys who actually do it. I've been taken down too many BS lightweight fixes before. This isn't a simple reboot of the ECU by pulling the battery cable fix.

I looked at the sensors. I didn't see anything amiss. This is a grocery getter, so it's pretty clean under there. No leaks. All looks good.

But do you think a broken sensor would stop the ECU from talking to Techstream? I'm going to try to clean the connections and check for broken wires around the ECU (when I locate it.)

 

[lx200inAR]

Thanks guys. I can assure you I did extensive reading on the subject. I've been on mud for 20 years and far enough along to have my own Techstream setup. I wouldn't dare come on here until I've done some leg work first. I read about some of these items, but I wanted to hear from the guys who actually do it. I've been taken down too many BS lightweight fixes before. This isn't a simple reboot of the ECU by pulling the battery cable fix.

I looked at the sensors. I didn't see anything amiss. This is a grocery getter, so it's pretty clean under there. No leaks. All looks good.

But do you think a broken sensor would stop the ECU from talking to Techstream? I'm going to try to clean the connections and check for broken wires around the ECU (when I locate it.)

The ECU is attached to where the brake fluid reservoir is. You may want to check FSM for tshooting power and possibly the CANBUS comms to the unjt. I agree it’s unlikely a broken sensor has caused the ECU to stop communicating unless it sonehiw shorted out the ECU.

 

[bmorgan]

The ECU is attached to where the brake fluid reservoir is. You may want to check FSM for tshooting power and possibly the CANBUS comms to the unjt. I agree it’s unlikely a broken sensor has caused the ECU to stop communicating unless it sonehiw shorted out the ECU.

This is my first dive into a 200 series, so thanks for being patient with me. I know every bolt on an 80. I'm a complete 200 noob.

I tested everything on the ABS ECU, verified power and ground, cleaned the pins, and rechecked with Techstream. Same outcome - all ECUs are talking but the ABS ECU. I was about to start looking at rebuilt, replacement ECUs.

BUT THEN, I noticed her radio wasn't working, so I called her about it . She said it hasn't worked in a while and she was going to ask me to look into that too. So now we have two electrical components out. THEN I saw the remains of a mouse down the between the battery and fuse box. It's dark down in there - didn't see it before. I looked at the radio fuses and they all look good. So I guess I'm about to pull the fuse box out to check for chewed wires. She's gonna owe me beer.

Thanks for the help, guys. I appreciate it.

 

[TheComedian]

Hm just from my experience. Right rear abs sensor/cable can definitely cause these lights in combination with no speedo wich I found out after dragging a half tree under my car and ripping off that cable (so it was pretty obvious luckily). Can also happen if water creeps into the cable causing copper corrosion wich I had on both sides till I changed a month ago the whole rear abs cable assembly.

Canr remember on wich manual it was but Toyota gives you infos what resistance you should get when measuring it since sometimes you cannot rly see if a cable is rly damaged and the measuring takes just a couple of minutes under the car so a easy checkbox to make the circle smaller…

But strange that you can’t connect to it via Techstream. Just to be sure (and I am sure you did but asking is better) you also tried different variants of the car in Techstream? Had the situation that on my 2008 deep Africa NGO spec I had to select the 2012 version to delete a lost key.

 

[bmorgan]

Since I found the mouse carcass, I thought I should look inside the fuse box. I pulled it all part and, besides a dead grasshopper, all was good. I rechecked the CANBUS voltages (high and low) and they were both at 2.51v - pretty steady. So I think that means we have a connected but not communicating canbus. And I'm guessing something is wrong inside the ECU.

I talked to the owner and the radio actually went out months ago. The ABS and brake lights just came on. So unless y'all have another other suggestions, I think we're looking at replacing / rebuilding the ECU. I'm happy to keep diagnosing, but what else can it be? If the ECU isn't sending information, but has power and ground...

 

[NikP]

Attached is the service manual diagnosis procedure for the skid control. I'm assuming this is the ECU based on what's been presented so far. Good luck.

At the end, one of the options leads to replacing the master cylinder solenoid. Might be worth a look.

I didn't see anything that leads replacing the skid control ECU or how to check it.