Replaced 12v battery, now brake fuse keeps blowing

If I was right about the fuses in this post, then ABS MAIN3 is the one that supplies the capacitor backup, so yeah, I'd be double-checking the connections back there,

 

There is a black box right next to the battery which has electrical wiring and says something about the brakes. Perhaps when the battery was changed the cable to this box was not securely reseated? Or maybe it isn't seated at all and that plug is shorting out to the body?

 

Indeed, that's the thing mentioned in post #1 and post #2.

 

Any update on this?

I am experiencing the exact same problem on my 2004. As soon as I try to replace that 15A fuse it blows and I have the yellow brake light warning on the dash.

 

UPDATE: Yellow (!) brake symbol is now cleared.

SYMPTOMS:
The car was braking fine, and the power brakes worked but the yellow (!) symbol was illuminated.

PROCEDURE:
The first thing I did was check the level of brake fluid in the reservoir. Level was GOOD
I next took off the wheels to check the status of the brake pads and looked for any loose or damaged connectors at the wheels - everything was GOOD
I next checked ABS fuses.

• ABS-1 (25 Amp fuse) - GOOD
• ABS-MAIN1 (10 Amp Fuse) - GOOD
• ABS-MAIN2 (10 Amp Fuse) - GOOD
  
• ABS-MAIN3 (15 Amp Fuse) - BAD

So I do the obvious thing and try a new 15-amp Fuse for ABS-MAIN3. It Immediately blows as I try to insert it (I can hear it "pop") - BAD

I already had a bad wire to the fuel pump in this car so I decided to check the wires. This circuit goes from this 15 amp fuse through a connector located near the passenger side kick-panel (connector is called IN1 in the manual) and then continues to connector B18 on the Brake Control Power Supply in the back of the car right next to the battery.

• The wire from the fuse block (outside pin) to the connector in the left kick panel is blue. I locate the wire and test the continuity. I get a nice loud beep. I then tested the continuity of this section with a chassis ground - no beep and no numbers. The last thing I do is check the resistance of the wire to ensure it is low - GOOD
• Next, I unplugged the wiring harness from the Brake Control Power Supply and tested continuity between the blue wire at IN-1 and the B18 connector at the Brake Control Power Supply. The continuity test was GOOD. I then tested for continuity with a chassis ground and no beep, finally resistance of the wire is low - GOOD
• I left both the connectors (IN1 and B18) both unplugged and went and installed a fresh fuse. The fuse did not pop and I verified it was OK with testing continuity across the fuse. I then tested IN-1 for 12V and was able to verify 12.6V at IN1 on the blue wire. GOOD
• Next, I plugged IN1 back in and tested for 12V at the rear of the car at B18 - 12.6V was verified. GOOD
• So at this point, I was fairly sure that the wire was OK the only thing left was to replace the Brake Control Power Supply.
• I got a used Brake Control Power Supply from a local salvage yard and installed it.
• I verified that the fuse did not blow and that the yellow (!) light did not come back on - SUCCESS!

BONUS: So I took the Brake Control Power Supply module apart to see if I could see any obvious defects (but marks or discoloration on any of the pins). One thing that I did notice was that the bolt that was holding the module on top was WAY longer than the bolt I got from the salvage yard. I could also see that the bolt on the old module had gone through the case and hit some metal that was near the circuit board. I suspect that this might have been the reason it was blowing fuses (I have not verified)

Anyway, I hope that helps someone else out.

Juan

 

Wow I like they style of write up. Very clear and easy to follow.