Do I need to do this repair?

My service engine soon light came on my 2001 BMW X5 3.0.the dealer said I need to replace the engine wiring harness for $1400!!They said it’s not crucial to do but might affect the gas mileage and may potentially be harmful to the catlytic converter>.Please advise

Why should YOU pay for BMW’s poorly designed electrical systems?? Drive on…

There are way too few details here. Exactly what is wrong? What was the code?

If it’s out of warranty, you don’t need to be going to the dealer. See an independent technician for a 2nd opinion.

“Service Engine” is just a nag light trying to get you to change the oil or something, right?

“Check Engine Soon”, the one that leaves trouble codes, is a different animal…

It’s impossible to give any advice at all when zero details are provided.

What codes are present, what harness is being replaced, what reason given for the harness replacement, etc. would be a good place to start.

An independent shop can splice wires to make repairs. Dealers can’t, or won’t. Properly done wire splices are just as good as replacing a whole wiring harness, and much less $$$.

The dealership didn’t give any codes to me.The only thing wrong was the Service Engine Soon Light came on.The car is driving ok.