weatherall123

I've been trying to look through the forums as well as scrambling through my Helms manual, but I haven't found a definitive answer yet. After troubleshooting for ABS code 1-2, it seems that I'll be replacing the ABS pump/modulator unit on my 1994 Honda Civic SI.

I'm wondering how to properly bleed the the brake system after this replacement. Would I first bleed the ABS modulator, followed by a standard bleeding at the four calipers?

I don't have the plug-in tool that is used in the Helms manual to bleed the modulator, so I'm wondering if the following would be an effective method:


Thank you in advance!

lazlong

The service manual makes no mention of bleeding the modulator but, that doesn't mean it's a bad idea. They do it because enough people have tried to bleed the system and ended up having to bleed the modulator anyways or it makes the entire bleeding procedure faster.

I have seen something like that done successfully before.

weatherall123

It actually does recommend to bleed the modulator whenever it is disconnected and/or replaced. In the Helms, they use a plug-in tool that, I believe, activates the pump/modulator for bleeding.

I'm just curious if I can bleed it using the method in the youtube video above. Also, should I bleed the modulator THEN standard caliper bleeding? Or should I bleed the calipers first?

lazlong

"6. After installation, bleed the air from the system." That's all the factory service manual says.

You don't need the plug-in tool, just use the jumper trick that the guy in the video uses.

Yes, it will work. Bleed the modulator first.

weatherall123

Since the modulator is part of the ABS system, I guess I am under the assumption that the service manual is telling us to bleed air from the ABS system whenever removing the modulator.

Anyways, as long as I have brakes after the replacement, I'll be happy.

tony_2018

If only there was a way to do this on the new abs bosch pumps....

weatherall123

Just because I like to understand why I'm doing things a certain way, does anybody know the rationale for bleeding the modulator prior to bleeding the calipers?

lazlong

If you do the calipers first then you're just sucking air bubbles from the modulator.

Nervosinho

I'm assuming that since the ABS Modulator is correctly assembled and it does part of the system, the bleeding of the calipers will work for the entire system, including the eventual bubbles that are inside the modulator...

lazlong

Hence why I said this earlier: