Antilock warning light

[gr8scott]

I took my first extended ride in mu recently acquired 88 Reatta. 240 miles round trip with several stops at the destination. After one restart, the antilock brake warning light came on and stayed on until I stopped a short distance away at a restaurant. The next time I started, it came on as supposed to, then turned off after 10 seconds or so. This happened several times in a row. Sometimes it would stay on, other times not. It never came on during operation of the vehicle, only at the start. I would think this is more of a warning light malfunction than an actual problem with the ABS system, but I thought I'd better ask for opinions.<P>While on the subject on brakes, I have another question concerning brake fluid level. I'm aware that pumping the brake pedal 25 times with the ignition off will refill the reservoir to a higher level. But at this point, the oil level is still about 1/2inch below the top of the reservoir. Should I refill it completely?

[Guest Brolliar]

The brakes are a touchy subject because a few forum members have had accidents when they have not worked properly. No one completely understands them.<P>First liquid level - My reservoir has a triangle pointing down in the plastic on the right side and a second triangle pointing up on a sticker below it. After the brakes have been applied with the key off 25 or a few more times to empty the accumulator the liquid level should be in line with where these triangles meet. On my car if I have not driven it for a few days the liquid is also at this level. After the key is turned on, the pump runs and then stops, and the liquid level should move down about 1/2 inch as the accumulator fills. <P>In a properly operating system on the first drive of the day the yellow light should come on when the key is turned on and then go off within about a minute. On restarts the light will go off much faster because the accumulator is already full or near full.<P>About your yellow light - if it goes out within a minute sometimes and never goes out other times you have a problem. It may be as simple as the main relay not always working. If the relay does not actuate the ABS computer does not power up and the ABS function is off. The yellow light being on could also be caused by other problems. If the yellow light is on from when you turn the key on and the red light goes on and then off normally the brakes will work properly, you just won't have ABS. Forum members have seen some exceptions to this where they did not have brakes when they neded them. Your drivers manual gives recomendations on what to do concerning the yellow light staying on.<P>My yellow light started not always going off but the car would still brake normally. I replaced the main relay and the problem was corrected.<P>There is alot of GOOD brake info<A HREF="http://www.reatta.net/brakes.html" TARGET=_blank>here</A>

[gr8scott]

Thanks for your detailed reply. Judging from your description as well as the excellent link provided, the safe thing to do is to replace the main relay, which I will do pronto.

[Guest Brolliar]

The GM relay that works and also mounts properly is #25530731. It is made for them by Hella. Its price at VanDevere Olds in Akron, Ohio is $9.14 plus about $5.60 shipping & handling. I dealt by phone (1-800-362-9494) with Dallas Slabaugh there. He was quite helpful. At my local Buick dealer the price was $26 and they also were going to have to ship it in. <P>This same relay is also used for the ABS pump motor. <P>There are some after market relays that work but I could not find one that would mount properly. If you can find a MR116 made by Hella it will probably mount OK.

[Barney Eaton]

If you do a search, you will find some new numbers for the MR116. Because some owners were told by AutoZone that the MR116 was discontinued I contacted Sorenson and published the new numbers. I would give you the new number but I have everything packed, going to Kokomo.<P>On the fluid in the resevouir... The level change is a function of the condition of the accumulator. A new accumulator will change the level about 3/8 inch (pressurized/unpressurized) As the accumulator looses its nitrogen charge, more fluid is forced into the accumulator, so there is a greater level change.<P>When the level change gets to 1/2 inch, I would be shopping for a new accumulator, when it gets to 9/16 you have little or no reserve.

[Guest]

where is the main abs relay located ? tim

[gr8scott]

Facing the car with the hood open, you'll see three relay boxes just to the left of the brake fluid reservoir, under the center of the windshield. The main relay is the one on your right.