I took my Supra to Sears to get the battery replaced (not sure why. it was close and i was in a hurry). I get back in the car and nearly half of the fuses are blown. I think they connected the battery backwards. I replace all the blown fuses and the head unit still won't power on (Pioneer AVIC-D3). Does the D3 have it's own fuse or did they really fry my deck?

Did someone there see that all of the fuses were blown BEFORE you took the car home? Seems like there is someone that 1) needs to be fired and 2) pay up for the damage.

Just in my logic of thinking, a fuse will accept bidirectional current. It seems to me that only a short or an overvoltage spike could cause a fuse to blow...not connecting a battery backwards. All I am really saying is, that more damage could be done that you are unaware of...and a Supra is a really sweet car! A fuse is not a fool-proof method and does not negate the possibility of PCM or ECM damage...as you are aware of as the D3 may have fried.

I would take it to a reputable mechanic and have them check for voltage/power damage. You may have an incompetence case against Sears.

Hope it works out! That sucks big balls!

They are aware of the issue. They did not openly admit to connecting the battery backwards (that's the only thing I can think of that would cause sooo many fuses to blow), but they seems to acknowledge that the car was in perfect running order before they got their hands on it. The ECU doesn't seem to have been damaged, but I haven't opened her up since the issue...

I'm taking her to a shop tomorrow to determine what's wrong with the deck. I'll have them do a complete electrical diagnosis to see if something else comes up.

It sounds more like they caused an unacceptable amount of arcing when replacing the battery.

The steps are...

Remove the Negative post first.

Remove the Positive post.

Remove the battery.

Clean everything.

Insert the new battery.

Attach the Positive post first.

Attach the Negative post.

If they follow these steps there shouldn't be arcing between the battery and the cables. If they didn't follow these steps then fuses and sensitive equipment in the vehicle could be damaged.

To answer your other question, yes, there is a fuse on the back of the D3. Try replacing that one too.

necros right.

but how did you test the fuses? just by looking or did you use a test light or digital meter?

always use a test light or a meter to test fuses the ol take a look see dont work anymore!

I just did a visual inspection on the fuses. I'll check the fuse on the deck next. If that's not it I'll use a meter to check the fuses. thanks!

Ya, I doubt it being backwards did this. I would guess they did a bad job installing the battery (like arcing) or way over or improperly charged the system. When you install a new battery you should "top it off". New batterys typically are at 85% to 90% charged sitting on the shelf. So if they put the charger on the wrong setting or hooked it up wrong it can mess stuff up.

Also check you alternator. If the voltage regulator has died or dieing you power will do all sorts of weird things. This can really harm electornices. Installing a battery wrong or giving a jump wrong can also kill your alternator / voltage regulator.

Good Luck.

you guys are so smart! thanks for your help!

Last Tip: Don't go at Sears anymore!!!!

Last Tip: Don't go at Sears anymore!!!!

Yup! I definitely learned my lesson!