ABS Modulator - (Master cylinder, Pump/Motor, Accumulator, Resivoir, Solenoid module) (1 Viewer)

[Jody Highroller]

Assumptions:
1. Brakes system operation: The 100 series Land Cruiser is designed so that braking operation functions normally (assisted braking, ABS) while the engine is OFF but voltage is available to ABS.


2. Diagnosing and testing the hydraulic pump/motor terminals for damage, refurbishing terminals (cleaning, crimps, lugs, fasteners) and subsequent bench testing to ensure pump/motor and solenoid module is operating normally.

3. Test solenoid controller box for continuity. Check electrical components signal paths. If solenoid controller box has internal component failure will attempt repairs.

4. Assumes accumulator has normal functionality if electric motor is operational.

Notes:
Verified power from battery and through ABS relays (cycling at idle). Verified 12 VDC up to connectors that mate to the AISIN solenoid controller box.

Removed brake pedal assembly and removed entire ABS Brake Booster Actuator Assy. component from firewall. The Solenoid Control Box and Electrical Motor terminals poured out water and rust when the rubber boot material covering terminals was pulled back from each of the terminals. The terminals are badly damaged as shown below.

 

[Jody Highroller]

After cleaning terminals.

 

[Jody Highroller]

Removed terminal screws from ABS electric motor/pump. Bench testing electric motor direct by applying 12VDC to ensure motor "bumps".

The motor did not respond when applied 12VDC power.

The electric motor was then taken apart and inspected for internal damage.

 

[Jody Highroller]

The single point kill is the ABS electric motor commutator wear. The failure mode is the electric motor brushes stop where the commutator copper is worn resulting in the electric motor's inability to start again. The failure effect is the motor fails to build system hydraulic pressure.

There is an inspection window covered with a rubber boot on the ABS pump. This boot may have pieces of copper commutator captured in the rubber boot indicating motor rotor wear damage.

An unexpected total loss of 100 Series Land Cruiser brakes may be mitigated by performing interval inspection of this boot.

 

[YardPig]

Excellent post and pics, thanks.

 

[Jody Highroller]

I am sending my electric motor to Electric Motor Repair, Rewinds, & Parts | Eurton Electric for repairs.



The following is a video of Eurotec processes

 

[sean2202]

Nice job. What did you clean your terminals with?

 

[dnp]

This is a critical issue with all 100s, especially those of ours with some miles on them. Therefore, whatever ended up happening with your write up? Was Eurton able to rebuild/replace the subject part(s) and solve your problem?

My 2000 currently has 311K miles on it, and I am constantly concerned about the possibility of the documented total brake failure associated with this system. My brakes work great right now, but I would still like to include this procedure in a preventative maintenance program if you've found a solution to the otherwise extremely expensive OEM parts swap.

Thanks.

 

[Jody Highroller]

This is a critical issue with all 100s, especially those of ours with some miles on them. Therefore, whatever ended up happening with your write up? Was Eurton able to rebuild/replace the subject part(s) and solve your problem?

My 2000 currently has 311K miles on it, and I am constantly concerned about the possibility of the documented total brake failure associated with this system. My brakes work great right now, but I would still like to include this procedure in a preventative maintenance program if you've found a solution to the otherwise extremely expensive OEM parts swap.

Thanks.

My opinion is that the electric motor failure (just wear and tear of the commutator) is going to be the main contributor to the failure condition.

Once the motor is unable to energize you will have no boost pressurization. You will get several alerts and codes that, I believe, comprise of this particular failure.

Contact Euroton electronics. They are phone and email friendly. The guy I delt with was Charlie. Also, you may be able to just buy a rebuilt Motor on eBay. I didn't see any motors for sale until after I sent mine to Euroton, but they're out there (sometimes)

Becareful With your flared connection upon reassembly. I'm dealing with this now. Major pain, man.

 

[dnp]

Thanks for the response.

Can you elaborate on what you're referring to when you say the "flared connection" and what problem you've encountered? Also, having gotten to the point where you are now, would you recommend going the route you did or would you recommend buying a complete new or used unit? Your major pain comment has got me curious.

Thanks again.

 

[2001LC]

Could dirt have possible been suck into bushing/bearings of motor because boot was torn, missing or damaged in some way?

 

[Jody Highroller]

Could dirt have possible been suck into bushing/bearings of motor because boot was torn, missing or damaged in some way?

No, it's just wear. It's a common failure mode of an elecrtic motor. The brushes and commutator over time just lose continuity due to copper destruction (friction and such) Toyota should do a 100k-200k replace as scheduled maintenance.

 

[Jody Highroller]

Thanks for the response.

Can you elaborate on what you're referring to when you say the "flared connection" and what problem you've encountered? Also, having gotten to the point where you are now, would you recommend going the route you did or would you recommend buying a complete new or used unit? Your major pain comment has got me curious.

Thanks again.

By flared connection I mean the stainless steel hardlines that use threaded compression nuts to connect to master cylinder.

Given the corrosiveness of Brake fluid, the tediousness of the ABS/brake system this job can seem easy but can fester and other problems can be created. For example, I changed the master cylinder pistion during this process. After placing the system back in and fighting the leaking cross thread connections, my pedal is now sticking. This is concerning to me because it indicates the master cylinder seals are sticking. Not sure though.

By all means if you do not have an adequate shop and tools but you do have the money pay a professional to do it.

 

[uHu]

Great info. Big tnx for sharing.

Two Qs:
WHat about bearings? How were the bearings of the motor? Can they be changed? Easily? ANy wear detected?
Any bearings or seals visible on the pump?

This inspection window on the pump is a bit unclear - How would debris from the motor get into the pump? Is there an open connection between the two?

 

[Jody Highroller]

Great info. Big tnx for sharing.

Two Qs:
WHat about bearings? How were the bearings of the motor? Can they be changed? Easily? ANy wear detected?
Any bearings or seals visible on the pump?

This inspection window on the pump is a bit unclear - How would debris from the motor get into the pump? Is there an open connection between the two?

My surmise regarding the inspection window on the pump is not conclusive. Can't remember if there was a channel clearly flowing from inside to out. However, I can say for certain both my friend and me saw copper pieces (from commutator) dangling from this orfice.

With regard to other damaged components. I can only speak for my situation. However, the only wear and tear item I saw was the commutator. The brushes were even remaining somewhat. My opinion remains, this issue is purely continuity interruption due to commutator wear.

 

[uHu]

DId you get your motor repaired? What was done? And how big was the dent in your pocket?

As I understand, everyone else agrees with you in that it's only the motor that wears fast, so a commutator and brush change should give it another lease on life.

 

[Jody Highroller]

I am sending my electric motor to Electric Motor Repair, Rewinds, & Parts | Eurton Electric for repairs.



The following is a video of Eurotec processes

UPDATE: Euroton repaired my motor and it is working.

However, upon reinstall I ran into other issues.

1. Compression fitting unable to connect properly. Now how as leaks.

2. Although I replaced mater cylinder, pistion and seals (~70 buck OEM part) the brake pedal is sticking to floor.

I believe the pedal stick is releated to the system not equalizing pressure and having air in lines.

 

[Jody Highroller]

DId you get your motor repaired? What was done? And how big was the dent in your pocket?

As I understand, everyone else agrees with you in that it's only the motor that wears fast, so a commutator and brush change should give it another lease on life.

The cost of Euroton to rebuild the Electric motor was 245.00 plus they charge about 20-30 bucks shipping. The motor comes returned with compete with new paint on housing, new insulator and Newspaper packing from Japan...(makes me wonder)

Also, by the video posted you can see and from observation they do a little more than commutator and brushes during the process. They do new winding and other parts. I find its good quality.

 

[Jody Highroller]

If anyone's where I can get OEM prefabbed/formed/flared brake lines and compression fittings please let me know.

I fortunately I believe I have damaged the seat of one of master cylinder port connections.

 

[Jody Highroller]

Well just to Update....

As I mentioned before the motor rebuild by the company in Cali worked.

I was able to get master cylinder compression fitting leak to a slight drip. Used new flared tubing and nut.

I also mentioned my new found issue of "pedal sticking to floor"

Well, it appears I found the problem.

Note, I fully believe my LC would be back on road had I not tried to be a preventive maintenance champ and change out the MC pistion, ya know "While I'm in there"

Upon pulling assembly from firewall and removing MC piston I found this.