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Flat Tire + Space Saver Spare = ABS & Brake Light?

2001 Ford Taurus; had a flat tire on my way to work today. Auto club came out and put on the space saver spare, but now the ABS & Brake lights came on while driving. They weren’t on this morning. I assume the little spare is causing this? (hoping anyway) Can anyone tell me for sure? New tires going on tonight!

Yup, the little spare is causing this. The wheel speed sensor on that wheel is sending the ECU a signal indicating that the wheel is turning at a significantly differenty speed than the other three. It is. The system is sending you a message that it’s detecting something wrong based on this odd signal.

Thanks, mt.bike! I assumed that was it, too much of a coincidence. Nice to have my suspicions confirmed.

I would agree and you might consider checking the air pressure in that space saver tire. They’re supposed to be inflated much higher than a normal tire and since they’re seldom used (out of sight, out of mind) there’s a strong possibility that low pressure on that T-type tire could be affecting it also.

I hope it’s on the back…Differentials don’t like those little spares for any length of time…I destroyed the rear end in a Crown Vic in 250 miles by using one of those…Never again…Plenty of room in a Vic for a full-sized spare…

Yes it was on the back, and getting the new tires put on turned the light off. I only drove it that way from work to the tire shop…maybe 10 miles total. Amazing what a difference a new set of tires makes. The old ones still had probably a good 1/4 tread left but were noisy and rough riding. I didn’t realize how bad until I drove with the new ones. Almost like driving a new car now!

Yes indeed, there is nothing like a new set of tires…