The ABS light has been coming on on my 2005 Nissan Altima. It doesn’t stay on all the time. It will not be on in the morning when I leave home, but will come on during the day of driving. The past couple of days we had colder weather. During those two days the light did not come on at all. Could a sensor be affected by temperature? The Nissan dealer says that they need to replace the entire system. Can the sensors be cleaned and would that help me problem?
Why are you going to the dealer?
Dealers are no better (or worse) than independent mechanics for almost anything you might need done on your car. They will almost always charge more per hour and often more for parts and supplies. They also tend to look at repairs a little different than the independent. A dealer may well recommend work that strictly may not be needed, but could be connected to the problem or maybe replace a part when a little repair would fix it ALMOST as good a new. There is no need to bring your car to the dealer for any service other than service that is going to be paid for by a recall or original warrantee. During the warranty period be sure to have all required (as listed in the owner's manual) maintenance done and to document all maintenance work. I suggest that most people would be better off finding a good independent (Not working for a chain) mechanic.
Note: Never ever use a quick oil change place. They are fast cheap and very very bad.
I suggest you get another opinion from an independent mechanic. A sensor could be bad, or there could be dozens of other reasons. Replacing “the whole system” seems a bit extreme, especially since the whole system consists of dozens of parts, if not more.
Get away from the dealer, find a good independent, and save some money.
“they need to replace the entire system”
Please allow me to translate that statement for you.
Roughly translated, it means…We have absolutely no clue, so we are just going to throw a lot of expensive parts at the problem and hopefully–by dumb luck–one of the replacement parts will fix the problem. And, even if all of that random work doesn’t solve the problem, the customer will have to pay our inflated bill..
Or, in other words, RUN from that dealership as fast as you can.
Find a well-reputed independent mechanic in your area for a much cheaper resolution to the problem.
An ABS system is pretty tough for a do-it-yourselfer to diagnose, but you can look at the parts that get the most abuse and see if there is any visible physical damage.
There will be a magnetic wheel speed sensor near each wheel that detects the teeth of a toothed wheel spinning past it. On the drive axle wheels, the sensors may be inboard, near the differential, rather than out near the brake. The toothed wheels should be straight, with no bent or broken teeth, and reasonably clean. The sensors should all be equidistant from their toothed wheels, and the wire leads should be intact and secured to the car.
If there is no visible damage, you will need a shop with expertise in this area to help you.