Yay! Glad it worked!

--Ian

Me too! I was really nervous about bleeding the system, but I think it turned out to be easier than I was expecting.

Note: I only use my Motive power bleeder to apply pressure to the fluid in the MC. I fill up the MC and pressurize it to about 10psi. I do not like putting fluid into the power bleeder tank because I feel that it can add a lot of air to the system and is a mess to clean up (especially if your MC bleeder cap doesn't seal well). I stop often and let the pressure escape from the tank to top off the MC fluid level, and I never let it go much below the full mark on the MC reservoir.

First, I bled the master, then cracked the fittings from the master going into the ABS block while using my pressure bleeder at 10psi. Once the air bubbled out of the inlet fittings to the ABS block, I pumped the pedal a few times, and cracked all of the outlet fittings from the ABS block and let the air bubble out (LF, RF, Rear). Bled the brake lines normally with the pressure bleeder and waited until I got a firm pedal. Then I started the car on jackstands, put it in 1st gear and let the wheels spin. I gave it a little gas and then stomped on the brake pedal as hard as I could. ABS cycled a few times, repeated this about 10x. Shut the car off, checked the MC reservoir, put the pressure bleeder back on and re-bled the brakes. I used a gravity bleed type bottle to catch the brake fluid and try to help keep the bleeders from sucking air back in. Repeat the ABS cycle thing a few more times, re-bleed brakes, abs cycle, re-bleed.

So far the pedal doesn't feel bad, but I haven't driven the car on the street yet since I have to put the rest of my interior back together from other projects. I am hoping for this weekend. I will probably be doing a few more bleed cycles too.

I had expected to go through a ton more fluid. Amazingly, I seem to have used less than 1L total to get where I am now. I had 1L unopened of pentosin, and now I have 4L of ATE. I bought way too much.:party:

isnt the real procedure for bleeding abs in this thread? grounding a wire and holding the brake or something I forget.

The specific procedure isn't in here, but it's something like that. Ground a wire on the diag connector, hold the brake down, turn key on and it'll cycle each channel in turn. Have a helper try to spin the wheel and verify that it turns at the right time. It's really loud and very obvious when it engages in test mode.

I had problems with it because I had a code in my ABS system (caused by a bad connection on one of my wires). If there's a code it won't engage the test mode, you need to clear it first.

The procedures are all in the 99 FSM, for which a PDF is linked in the sticky section.

--Ian

I have the 99-01 FSM. I read the clearing DTC procedure.

And I found that bleed procedure too. Last time I looked, I had an empty hole in my diagnostic box under the hood on my 2000 and no TBS wire. WTF. I'll look again.

if you retrofitted then you probably didnt connect that wire to anything when wiring it up. Just find that wire and ground it. I ended up with like a 6" pigtail when I got my abs retrofit bits and just didnt connect the wires I didnt need/didnt have the harness for.

I hooked mine to TBS by swiping the pin in the diag connector for the cruise control. I melted the cruise at Laguna one day and since I have a trailer for it I never used it anyway, so I just ripped it out.

But yes, a pigtail works fine too.

--Ian

I got the pump out of a 2004 MSM, which should be the same as the 2003 pump that Codrus used. I also got a 6" pigtail with mine.

Fixing it should be easy enough.

Thanks for the help Ian and Leafy.

EDIT: Fixed it. It was the brown wire going to the data link that is the TBS. Cycled the ABS a lot. Drove it. Pedal feels like poop. Need more cycles.

Hi guys,

I just started the ABS swap myself on my 04, today i mounted all the lines and the Pump. I had no issues with any of the lines, I routed the long rear line from the bottom of the car and was able to persuade it to fit. The lines are very flexible, you just have to make sure not to bend them too much.

Thanks for the great post!

Old thread, yes, but relevant to my current interests, still the best thread of its type on the web, and I will update with my own install details once the install is complete.

I'm wiring my ABS at the moment. I have a question about the two grounds coming out of the abs brain connector:

Wire A, black, runs to ground G202 behind left side of dash
Wire D, black/blue, runs to ground G203 behind right kick panel.

Any reason I can't just ground those together at a convenient ground somewhere?

In theory, the ground should go where they are supposed to avoid <insect electronic jargon>. I wired the grounds together as you suggest with no ill effects.

This is an NB1 ABS system?

On my car with the retrofit NB2 unit (combo brain & hydraulic unit) I took all the ground wires and grounded them all to the chassis at the same spot right next to the bracket that holds it.

--Ian

It's an NB2 system, from my original '01 car. I'll just do that then. I couldn't think of a reason electrically why the grounds would be affected if they were grounded separately or tied together, but since Mazda ran them separately I thought I'd ask. Thanks.

My guess would be that one of the grounds is for the power stuff and the other is for the electronics and they're grounded separately in order to reduce the chance of any potential electrical noise from the pump getting into the electronics. Does it actually matter? I have no idea, but I didn't bother to do anything special with them and it doesn't seem to affect the way mine runs.

--Ian

Mine go to the same ground and just to some random threaded hole in the NA chassis near the abs pump.

I was about to start the final pigtail wiring connections today and I realized I have overlooked something.

Pin V, Grn/White wire, goes to Datalink Connector (engine bay), Datalink Connector 2 (lower left of dash, is this the OBD2 connector?), and PCM (behind left side of dash).

I know what the Datalink Connector line does, grounding that is how we cycle the unit.

a) I don't know what the PCM is
b) Does it matter if I don't run that connection?

I was expecting just to ground the green/white wire whenever I wanted to bleed the ABS unit properly, but if I need the PCM connection, I might man-cry. I just re-installed the MS3 and started buttoning up under the dash.

Diagram is in post 3: https://www.miataturbo.net/build-thr...9/#post1025301

PCM is "powertrain control module", it's the ECU. I didn't hook mine up to the ECU (the megasquirt doesn't have a clue what to do with it). I don't know what that connection is for -- perhaps the factory ECU can pull codes from the ABS module and transmit them over OBD?

I don't think it's important.

--Ian

Ah. Ok, great. I'm also megasquirt, so that wire is dead to me as well.

Feels weird I could be on this board for 10 years almost and not associate PCM with ECU.

You do need to connect to the brake switch circuit though at least to do the bleeding produce with the holding the brake pedal while cycling the key I'm not sure if that has a functional effect on the ABS and I dont want to test it.

Yeah, if the input from the brake pedal switch isn't there it'll throw codes.

--Ian