Help - occasional ABS light and humming black box

[motorbobb]

I have a 94 Q45t. Over the last six months, on a few occasions the ABS light came, and stayed on. The light seemed to come on not as a result of braking (ie the pads feel strong) but when the car was started.

The odd thing is that when the car is turned off, a humming noise continues to come from the little black box next to what I think is the ABS unit (passenger side of the engine compartment near the firewall).

How have I got the humming to stop?? Good old fashioned american ingenuity -- a soft tap on the black box with the palm of the hand.

I am guessing that the black box is some sort of electrical relay for the ABS and that the relay is wearing out. However coming from someone who has resorted to fixing the problem by pounding on it, its obvious I need some expert advice.

Any idea about potential fixes and the costs? rgds kc

[maxnix]

Check the ABS relay.

Have you flushed the brake fluid yet? Old moist fluid causes ABS unit to fail, then big repair bill to owner.

[driverdriver]

If its the ABS relay/pump, it should be a failry straightforward DIY job after buying the part from a Nissan/Infiniti dealer(they're only availabe there).

[artandscience]

I had the same problem. There are two relays in that area that work with ABS. If one goes bad (as mine did), it will continue to humm and consume power even after the ignition is off.

I replaced both relays with new ones at the same time. I think it was about $35 per relay (not cheap) but that fixed the problem.

[Q451990]

I would check with Scottsdale on relay prices, but in all honesty I think they're pretty standard as far as automotive relays. You might try to buy one locally at AutoZone, etc...

Heath