Fix for ABS, VSC TRAC, VSC OFF, & Brake lights remain on no CEL, or how to repair an ECU (1 Viewer)

[wrav001]

This post is a one of the best that I have come up on the internet. Good Job.. I had the same lights VSC, ABS, EM breaks, and one more on my 2001 Landcruiser Cygnus (LX470 for American market) Went to TOYOTA dealer and code was no ABS/VSC/TRAC connected. Came home and google for and came up with this post.

Pulled the 89540-60150 ABS TC and VSC unit. Immediately could seen some water ingression and corrosion. Pins on main 3 ICs had mold looking moss on it. I cleaned it with WD40 contact cleaner (bad idea as it melted the glue on circuit board) Should have washed it instead.

As mentioned here I have tested the X3 oscillator and looks to be the culprit. I live in Sri Lanka and only place I order electronics is RS united kingdom. The part will take a week to come. I will update the progress..

 

[FJRyder]

Immediately could seen some water ingression and corrosion. Pins on main 3 ICs had mold looking moss on it. I cleaned it with WD40 contact cleaner (bad idea as it melted the glue on circuit board) Should have washed it instead.

That water/moisture damage looks pretty bad. The clear, rubbery coating you removed is to prevent corrosion (not glue). Ideally, you should replace it with something like these: Cortec ElectriCorr VpCI-286 Acrylic-based Conformal Coating for Printed Circuit Boards or MG Chemicals - 422C-55MLCA 422C Silicone Conformal Coating 55 mL Bottle

Please let us know how it goes.

Also, for anyone else having this issue. I have found this exact same problem on other Toyota products, like the 4Runner and Lexus SC430. Probably any Toyota product used between 98-2005 or so uses the same or similar computer module with this faulty resonator.

 

[wrav001]

Bad part measurements in circuit (center pin = ground):
Left pin to center pin (gnd) = 8.73k ohms
Right pin to center pin (gnd) = 7.96 ohms
left pin to right pin = 777 ohm (this should be open or infinite)

Thanks for all the advice you have been giving here..

So before me washing the board with WD40 contact cleaner I was getting pretty low resistance between left pin to right pin, something like 200ohms..

After using contact cleaner and drying it for couple of hours I am getting following readings.

Left Pin to Center Pin = 19.61 M ohms

Right Pin to Center pin = 8.71 K ohms

Left pin to right pin = 19.12 M ohms

I have repeated the above tests multiple times as I only have a 20year old Klein multimeter. It is costing me nearly US$65 and 2weeks to get a oscillator for RS components UK. (minimum order quantity 20 and GBP 22 for shipping). I know this is still way cheaper than buying a unit but doesn't feel good paying so much for something so little. So was wondering above numbers are any sign of a good oscillator. I don't have a test rig to power this unit nor a oscilloscope. Thanks...

 

[FJRyder]

o before me washing the board with WD40 contact cleaner I was getting pretty low resistance between left pin to right pin, something like 200ohms..

After using contact cleaner and drying it for couple of hours I am getting following readings.

Left Pin to Center Pin = 19.61 M ohms

Right Pin to Center pin = 8.71 K ohms

Left pin to right pin = 19.12 M ohms

200 ohms is definitely bad.
My suspicion is that this is a mechanical failure of the resonator. If this is the case, then any movement or physical force on the resonator *may* place it back in a 'good' condition. If that is the case, it would be an intermittent state and likely fail again.

My recommendation is to plug it back in and try it. Then, when the part arrives, replace it. If it is working now, then you know it will be fixed permanently when it's replaced.

 

[wrav001]

200 ohms is definitely bad.
My suspicion is that this is a mechanical failure of the resonator. If this is the case, then any movement or physical force on the resonator *may* place it back in a 'good' condition. If that is the case, it would be an intermittent state and likely fail again.

My recommendation is to plug it back in and try it. Then, when the part arrives, replace it. If it is working now, then you know it will be fixed permanently when it's replaced.

I have tried it but no luck. Do I have to clear the fault codes after installing it? I ve tried removing battery and also shorting E1 and Ts.. but nothing is blinking. Nearest Toyota dealer is about an hour away.

After bit of contemplating on whether to buy a resonator for almost US$70 or buying a Unit for US$170 (From United Arab Emirates, including shipping) , I have decided to go with buying a unit from UAE. 4hour flight to Sri Lanka and I should get it reasonably quick. Lets see how I go... Thanks

 

[FJRyder]

I have tried it but no luck. Do I have to clear the fault codes after installing it? I ve tried removing battery and also shorting E1 and Ts.. but nothing is blinking. Nearest Toyota dealer is about an hour away.

After bit of contemplating on whether to buy a resonator for almost US$70 or buying a Unit for US$170 (From United Arab Emirates, including shipping) , I have decided to go with buying a unit from UAE. 4hour flight to Sri Lanka and I should get it reasonably quick. Lets see how I go... Thanks

Nothing needs to be reset. When it's fixed, all lights are off.
You may want to double check fuses are also good.

 

[wrav001]

Nothing needs to be reset. When it's fixed, all lights are off.
You may want to double check fuses are also good.

Cheers for your advice. Checked the fuse and it is OK. Took the unit off today. Buggered resonator giving 200ohms from 1 to 3. I am still amazed that you managed to identify this generic issue. I am a retired power systems engineer, retired at 35 after doing12years of Digsilent power factory simulations and electricity spot pricing analysis. I worked as a solderer and assemby/VHDL programmer when I was a student 20years ago. I got lucky in property flipping and day trading and decided to be a full time organic vegetable grower now. I think, I need to get back in to my true love of electronics again..

 

[wrav001]

Replacement unit arrived.. Tested the resonator and was good. Replaced it and all codes are gone.. Cheers for this thread on helping me to identify the issue..

 

[FJRyder]

Replacement unit arrived.. Tested the resonator and was good. Replaced it and all codes are gone.. Cheers for this thread on helping me to identify the issue..

This is great news! Glad it all worked out for you.

I am still amazed that you managed to identify this generic issue. I am a retired power systems engineer, retired at 35 after doing12years of Digsilent power factory simulations and electricity spot pricing analysis. I worked as a solderer and assemby/VHDL programmer when I was a student 20years ago. I got lucky in property flipping and day trading and decided to be a full time organic vegetable grower now. I think, I need to get back in to my true love of electronics again..

I have been a RF design engineer/manager for the past 21 years. My process is to always start with the basics, power and clock. I was first looking for any potentially bad electrolytic caps as that seems to plague many electronics from the late 90's early 00's. I got lucky with the clock/resonator. I'm amazed at just how widespread an issue this is. It's one of the disadvantages of using almost the same design on all products. Mistakes are propagated everywhere. Great job on becoming independently wealthy. How was the transition from tech world to the agriculture world? I'm thinking of doing something similar.

 

[J100LX]

@FJRyder

Fantastic writeup!

I’m running into a snag near the end (hopefully) of the process…

1. The five lights displayed with no other known symptoms (ABS, TRAC, VSC TRAC, VSC OFF, BRAKE).
2. With Techstream hooked up I get the “*ABS/VSC/TRAC” displaying, and when I click on it I get the “Select system is no responding or not available. Please check the repair manual for applicable systems." error message.
3. I removed the skid control ECU (89540-60160) and shipped it off to G7 Computers.
4. They confirmed that the hardware was damaged. "The computer you sent here has been repaired. There was a hardware failure on the board." They repaired the hardware and shipped it back.
5. I reinstalled the ECU (89540-60160) and turned the car on and drove it around the block. All of the 5 error lights still remain illuminated.
6. Hooked up tech stream and it still displays the same “*ABS/VSC/TRAC” connection error as before.

Any other ideas? Thank you in advance!

*edited post with added part numbers for clarity.

 

[wrav001]

@FJRyder

Fantastic writeup!

I’m running into a snag near the end (hopefully) of the process…

1. The five lights displayed with no other known symptoms (ABS, TRAC, VSC TRAC, VSC OFF, BRAKE).
2. With Techstream hooked up I get the “*ABS/VSC/TRAC” displaying, and when I click on it I get the “Select system is no responding or not available. Please check the repair manual for applicable systems." error message.
3. I removed the ECU and shipped it off to G7 Computers.
4. They confirmed that the ECU hardware was damaged. They repaired the hardware and shipped it back.
5. I reinstalled the ECU and turned the car on. All of the 5 error lights still remain illuminated.
6. Hooked up tech stream and it still displays the same “*ABS/VSC/TRAC” connection error as before.

Any other ideas? Thank you in advance!

As FJRyder would confirm it is not the ECU but the ABS/VSC/TRC control unit part number 89540-60150 (1999-2002) or 89540-60160 (2002-2008) Cheers

​

 

[J100LX]

As FJRyder would confirm it is not the ECU but the ABS/VSC/TRC control unit part number 89540-60150 (1999-2002) or 89540-60160 (2002-2008) Cheers

​

Thank you for the reply. The unit that I removed, had fixed by G7 computers, and then reinstalled is the 89540-60160 unit (pic attached).

 

[wrav001]

Thank you for the reply. The unit that I removed, had fixed by G7 computers, and then reinstalled is the 89540-60160 unit (pic attached).

Since I had the same issue last week and fixed it yesterday, here were some of the things I did;

1. Check all the fuses and relays for good measure.
2. Unplug the ECU(89661-60610), then the VSC,TRC TRC unit and then the ABS unit wiring at the engine bay.
3. Check all sockets and wiring for loose connections and damage.
4. Clean all sockets if required and re plug.
5. Still not working replace 89540-60160 (US$200) I wonder how much you paid for G9 to repair. I had no option to repair as couldn't get a resonator.
6. Still not working replace the ECU and test continuity of wire harness between ECU and 89540-60160

I found it replacing these parts by myself is way cheaper than taking it to the agents. One visit to agent cost more than replacing parts.

My gut feeling is you need a reconditioned 89540-60160.

 

[J100LX]

Since I had the same issue last week and fixed it yesterday, here were some of the things I did;

1. Check all the fuses and relays for good measure.
2. Unplug the ECU(89661-60610), then the VSC,TRC TRC unit and then the ABS unit wiring at the engine bay.
3. Check all sockets and wiring for loose connections and damage.
4. Clean all sockets if required and re plug.
5. Still not working replace 89540-60160 (US$200) I wonder how much you paid for G9 to repair. I had no option to repair as couldn't get a resonator.
6. Still not working replace the ECU and test continuity of wire harness between ECU and 89540-60160

I found it replacing these parts by myself is way cheaper than taking it to the agents. One visit to agent cost more than replacing parts.

My gut feeling is you need a reconditioned 89540-60160.

Thank you for the troubleshooting ideas, I really appreciate it!

The G7 repair price was $275 +shipping one-way.

 

[FJRyder]

@FJRyder

Fantastic writeup!

I’m running into a snag near the end (hopefully) of the process…

1. The five lights displayed with no other known symptoms (ABS, TRAC, VSC TRAC, VSC OFF, BRAKE).
2. With Techstream hooked up I get the “*ABS/VSC/TRAC” displaying, and when I click on it I get the “Select system is no responding or not available. Please check the repair manual for applicable systems." error message.
3. I removed the skid control ECU (89540-60160) and shipped it off to G7 Computers.
4. They confirmed that the hardware was damaged. "The computer you sent here has been repaired. There was a hardware failure on the board." They repaired the hardware and shipped it back.
5. I reinstalled the ECU (89540-60160) and turned the car on and drove it around the block. All of the 5 error lights still remain illuminated.
6. Hooked up tech stream and it still displays the same “*ABS/VSC/TRAC” connection error as before.

Any other ideas? Thank you in advance!

*edited post with added part numbers for clarity.

Hi J100LX,
Did G7 diagnose and determine that this resonator component was bad? Did they explain what was repaired? If not, maybe get a detailed explanation.

If the repaired ECU is actually good, then the problem likely lays somewhere in the connectors and wiring. However, if G7 says they fixed it, meaning there was something wrong in the first place, it seems unlikely (but not impossible) that you ALSO had an issue somewhere else.

Do you know anyone else with the same LC series that you can try swapping the ECU out with? This maybe the best test to determine if the issue is somewhere else in the vehicle. There is no programming or memory swap needed to do this. These ECUs are plug and play as long as the part number is the same.

Good luck!

 

[J100LX]

@FJRyder Thank you for all of the ideas and pointers, appreciate your time!

No detailed explanation from G7, other than that it was faulty and they repaired it. Good idea to ask them for more details.

Also a great idea to swap the module with a friend.

 

[J100LX]

[duplicate post deleted]

 

[J100LX]

After further troubleshooting emails G7 has graciously offered a refund (without me even asking for one).

They had more feedback; "There must be an intermittent or latent fault inside the computer. The nature of intermittent faults are that they appear and disappear at random, and therefore make it very difficult (sometimes impossible) to detect." I imagine it is impossible to fully diagnose without them having access to rest of the vehicle.

Even though it didn't quite workout for me, G7 was professional and easy to work with throughout. They even put a rush on the return shipment at no additional charge to compensate for the holiday last week.

I've ordered a used replacement 89540-60160 unit off eBay, so hopefully that route does the trick.

 

[FJRyder]

After further troubleshooting emails G7 has graciously offered a refund (without me even asking for one).

They had more feedback; "There must be an intermittent or latent fault inside the computer. The nature of intermittent faults are that they appear and disappear at random, and therefore make it very difficult (sometimes impossible) to detect." I imagine it is impossible to fully diagnose without them having access to rest of the vehicle.

Even though it didn't quite workout for me, G7 was professional and easy to work with throughout. They even put a rush on the return shipment at no additional charge to compensate for the holiday last week.

I've ordered a used replacement 89540-60160 unit off eBay, so hopefully that route does the trick.

From my experience, replacing the resonator has been a solid, permanent fix for the past ~2.5 years. So I'm surprised they would say that.

I hope the new unit works for you!

 

[J100LX]

From my experience, replacing the resonator has been a solid, permanent fix for the past ~2.5 years. So I'm surprised they would say that.

I hope the new unit works for you!

The replacement unit 89540-60160 fixed the issue! Thanks for the time and your expertise/responses!

Just plugged it in the replacement and all five dash lights went off. Boom!