2003 MCS 31,000 mi. I just noticed today when backing out of the garage that the back up warning system was not working.Any common problems for this issue?
Thanks in advance

 

The backup sensors use the same fuse as the power steering fan. It's a common problem for the power steering fan to fail and blow the fuse, which takes out the backup sensors at the same time. Check the fuse and also your power steering fan. The fuse seems to be either F40 or F41 depending on year: https://www.northamericanmotoring.co...5amp-fuse.html

 

Should the power steering fan be spinning whenever the car's running? My backup sensor fuse has blown twice since my car was new (75k miles & 4 years ago), so I guess I should check to make sure there's not a problem with the fan.

 

I replaced the fuse the back up chime worked for about 20 seconds and stopped my guess would be the fan is the problem

 

Today was the 1st chance I had to look at the car.Jacked it up and the fan seemed to turn freely with my finger.Took it out of the car and hooked it to a battery from my other car.The fan seemed to work fine.I put in a new fuse started the car and put it in reverse while the fan was not in the car still no warning beeps.I thought maybe the fan had to be connected so I put it all back together still no beeps and no fan spinning.I swapped the fuse from the mirrors to the fan to make sure the fuse was good.The mirrors work fine with either fuse.Seems to be some sort of wiring problem.Anyone heard of anything like this ???

 

Any damage to the rear bumper? Any sensors scratched? Sometimes the system can act up.

 

^^^^
No damage they all look fine

 

Just remembered just before this problem I waxed the car.Just went and looked and there was a tiny amount of wax build up around the outside edge of the sensors.Cleaned it of and now they work...but still no fan.Is it supposed to run all the time????