Hi all. I have the dreaded Bendix 10 brake system on my 1992 Caravan, and the system recently acted up with the common "no brake assist" fault. The brake assist on this system is through the ABS hydraulic assembly (no vacuum). I had another hydraulic assembly (which includes the master cylinder) sitting around, so I had my mechanic install it, and we bled the brakes. While the replacement hydraulic assembly still brings the ABS and BRAKE warning lights, I DO have brake assist now, and I have an appointment with the dealer for further diagnosis as this system has a recall.

But where I'm stumped is, since this bone-yard unit got installed, the brake pedal doesn't return completely. Hence, the rear brake lights stay on. I have to lift the pedal about 1/2 inch to 3/4 inch with my foot or hand to get a complete return and for the rear lights to turn off. I've been back to the mechanic 3 times, and he played around under the dash with a screwdriver and WD40, and each time he improved it. The improvement would last until I'd get home, and that's about it.

The mechanic tells me that the hydraulic assembly may not be powerful enough to return the pedal all the way back. This is all new to me, as I've never had a master cylinder give me a problem before (lucky I guess), so I don't know what to think with this. Any thoughts on cause possibilities would be appreciated! Thanks so much.

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