06tangGT

06 GT - HELP! - Fuse #42 blows when turn key on, codes u1900 2100 b1317... Also DTE ODO data error check charging system message... It's got over 200k miles, been running fine until recently had some knocking - changed all spark plugs and coils. Have had LOTS of accessories hooked up to both cigarette lighters, few days ago new battery swelled and sprayed acid... Got new battery in now... Car wants start but everytime turn key fuse 42 blows (pcm or engine 3)....also get DTE ODO data error message check charging system. Codes b1317 u1900 2100....PLEASE SOMEONE HELP, I'M LOW ON MONEY, CAR IS MY LIFE LINE. HAVE PLENTY TPPLS BUT AVG EXPERIENCE. READING FORUMS WITH LOTS DIFFERENT FIXS BUT SLIGHTLY DIFF Scenarios..... I think maybe fuel system electrical or maybe bc so many accessories hooked up...

Dino Dino Bambino

The battery swelling up and exploding is a sign that it's being overcharged. Therefore either the alternator regulator is at fault or, more likely, a rectifier diode is at fault and allowing excessive AC current to leak into the main engine wiring harness.
I suggest you also check the B+ wiring harness from the alternator to the battery in case it's chafed and shorting out somewhere.

06tangGT

So what are my options in regards to fixing the diode issue? Or what should I do in order to get this problem fixed quickly and cheapest... Cost wise what am I lookin at?

Dino Dino Bambino

If you have a digital multimeter, you can perform an AC ripple test to determine if an alternator diode is indeed at fault. There are a few videos in YouTube describing the procedure.
If indeed there's a bad diode, you'll need to replace the alternator. The best choice would be a Denso version from an 09-10 GT.