The caliper locked up and ABS had been coming on off for a couple months. Caliper did release but now pedal goes to the floor. Mechanic says I need the whole unit (part JLM 1475) , master cylinder and ABS combo. Fuse is good but zero hydraulic and no pump noise. Part is hard to find and very expensive. Mechanic seems “brake” qualified but not specific to Jags. Not sure if I should tow it to British mechanic in DFW or other ideas. Thanks for your thoughts.

 

Hi Mikone

Are you absolutely certain that your Car is a 1995 as Cars that year had a separate Master Cylinder to the ABS which was a standalone unit on the opposite side of the Car

Although in any event I wouldn't start panicking yet, as while you may need a new Caliper or New Pistons put into the one that you have on your Car, where replacing the Caliper is a fairly easy job

The Chances are that all that happened is that the Brake Fluid got so hot with the Friction that it Boiled and that is the reason that your Brake Pedal went to the Floor, which was something that happened to me on my 1990 which does in fact have the JLM 1475 which are NLA

Though do fear not as fixing that is a very easy repair that shouldn't cost you more than a few dollars, so in the event it turns out to be that, then come back and I'll show you how to fix it for next to nothing

So First Job get a New Caliper or a Service Exchange one or New Pistons put in the one that you have on the Car, which you are almost certainly going to need anyway, together with New Brake Pads for both Sides of the Car

Then having done that Bleed the Brakes and if you're lucky that will fix it and you'll be good to go

 

OB,

The US naming of model years means that Mikone's "95" car was built in 1994 and will have the complex Actuator Unit setup rather than a Master Cylinder. The part number JLM1475 also indicates that it's the earlier Teves ABS system that you and I know so well!


Mikone,

OB is correct. Don't think about trying to buy the combined Actuator Unit (JLM1475) just yet. 2 reasons:
- it's ludicrously expensive, even as a reconditioned item. (They haven't made any new ones for 20 years.)
- more importantly, I suspect it isn't the problem.

Your comment that the accumulator pump isn't running is also concerning as that should be running even if your actuator unit was failing.
The Teves system is very complex. So, if you've had a failed caliper, I would start as OB suggests by bleeding the whole system PROPERLY. That means you need to start by bleeding the low pressure side of the side of the system. Let us know if you don't know what that means.

After that, I would start the process of bleeding the rear brakes using the recommended Teves procedure. Again, shout out if you don't know what that means. BUT, if the pump doesn't start to run as the first part of the procedure, Stop and don't bleed the rear brakes. You then need to start examining the pump failure reason.

Hope that helps

Paul

 

It’s still at mechanic. I’ve sent him both of your replies and thanks you. With the ABS light coming in before the caliper froze, makes me wonder if the expensive part was already going out. The caliper did release after cool down but he still hasn’t got any power from master cylinder/Abs combo. I’ve asked him to bleed brakes starting with lower side first. Do you think replacing the caliper and bleeding could start the system back up?

 

Hi Mikone

Anything is possible but maybe it could be the Pressure Switch that cuts out the Brake Pump when Brake Fluid Pressure is reached that needs replacing, that's the Gold coloured Tube that sticks out of the side of the Brake Pump

I think you can still buy this Part ptjs will know

 

Mikone,

If it were me, I would look at it in the following order:

- Bleed the low pressure side of the system, this is the fluid feed to the accumulator and pump.
- Press the brake pedal 20 times to try and discharge any residual accumulator pressure that may exist in the system.
- Turn on the ignition and see if the pump starts to run.
- If the pump doesn't start at all, I would start looking for confirmation of power to the pump.
- Then come back and let us know what is the status of that pump operation

- Do not try and bleed the wheel circuits if you don't have accumulated pressure built up. You have to use the pumped fluid pressure to bleed the rear brakes. And you MUST bleed the rear circuits the correct way. The Teves ABS is not a typical brake system

The pressure switch that OB refers to is not available from Jaguar, but there may be other avenues to source that.

Cheers

Paul

 

Mechanic said line was blocked with bad fluid and then air build on tire side of line. System powered back up after the flush. Caliper and line replaced and complete fluid flush. Anti-lock light is still on so not sure what to make of that. Thanks for all your help. The mechanic used your ideas. !