Remove battery cable for audio component install?

[t-bone1924]

Hello, new 2004 S40 1.9T bought last month with 77K miles.

I am installing an aux input accessory via the CD-changer port on the HU-555 radio. I am concerned about whether to disconnect the battery for the install. I have read about problems in doing so with or without battery disconnect. Seems that if you disconnect a component while battery connected (or cycling ignition) you get a code and light that dealer needs to reset. Alternately, I read that you sometimes get SRS warning lights on older cars when battery power dies/problems with SRS computer, etc. which also need dealer intervention. I have the radio code already so I have that covered.

I am looking for a quick EASY install with unnecessary dealer cost! What say you all?

[osman]

The newer the car the greater the chance of the anticipated problem. SRS light usually only comes on if you dont disconnect and replace ; seat, seat belt tensioner, airbags , steering wheel, etc. Components of the SRS.
I would play it safe. Takes 5 seconds to disconnect a battery.

[bwinkler]

I agree, when doing anything with electrics in cars all the literature says to disconnect the battery. You could also think of it this way: keep it connected and you can fry yourself or a component. Disconnect it and you just have something that doesn't work afterwards that can be fixed - or reset codes/lights.

My experience is on the 850 I had to reset a code, on the XC70 it went fine but a friends S60 who replaced the dash and didn't disconnect the battery had to take his to a dealer to get the warnings removed.

Cheers,
Ben