Hey!

I'm currently stuck scratching my head with the Pontiac Firebird 89 2.8 V6 model regarding circuit breakers. The Service Manual says to use 35AMP circuit breakers, but i currently have 30AMP's installed. While searching the web, i can't seem to find anything that goes actually over 30AMP's. There are 20,25,30AMP circuit breakers, but not 35AMP. What gives? Can someone please help me with this? Is the Service Manual wrong? If you know any place to get a 35AMP i would gladly appreciate it.

PS! Yes i know, in theory it shouldn't matter, because it just gives less power to the module (and it can heat up the circuit breaker), but why did the Service Manual writers write 35AMP circuit breakers. Is it their wrong?

All the pictures are added in the attachment.

Dr34m

 

The 30 amp breaker doesn't "give less power" than a 35. All it does, is trip at a slightly lower current draw.

Shouldn't make the slightest difference.

It may be that GM had 35s special made just for the production line, because some ONE thing somewhere (maybe not even in one of THESE cars!!) needed it, so they just made em all that way. Since the main purpose of a CB is to protect the wire from catching fire in the event of a fault, the difference between 30 & 35 didn't matter anyway.

If they aren't tripping, it doesn't matter.

 

Yeah sorry for explaining it wrong. Yeah you are right, if the current goes over 30AMP then it just trips. Well currently the blades looked just oxidized and i scraped it off with a sandpaper. It is though weird that even the official OEM from GM is actually 30AMP, but the manual says 35. Probably yeah was meant for those turbo versions or something. Who knows. I guess ill stick with the 30AMP's then, otherwise need to go the junkyard to find one .

What do you think about fuses that have exceeded the AMP mark. For an example the CRANK fuse. I don't have a 3AMP fuse and im using a 5AMP one. That 2AMP differential shouldn't do nothing right? Well with exceeding AMP's i guess the risk is that you can burn the module right? For an example using 30AMP in a 3AMP fuse. What is your opinion on it?

Dr34m

 

Fuses and circuit breakers do absolutely nothing except in the instance of a short. (pinched wire, or one damaged where the metal touches grounded metal, or the like) The rest of the time they have no effect on anything.

I would not put a 30A where a 3A goes, because if there WAS a short, it's entirely possible that the fuse would NOT blow, and the wire could get hot and melt, or even catch fire. Substituting a 5A where a 3A goes is probably not a problem though.

 

When I worked at the dealer, I was busy working on a Cadillac, so my Service Advisor gave my next job to the Engine guy. That next job was a blown fuse, it would be real intermittent and random. The moron took the 15A fuse out, stuck a 30A breaker in there and filled the truck with smoke, melted the IP harness from the driver side, across the bottom of the dash, up, across the top of the dash, and back over to the steering column where the wire pinch was at. Worst part about it was the jerk pawned the job back on me, so I had to pull the dash and replace the whole IP harness! So be careful substituting circuit protection (fuses or CBs)
In your specific instance of 5A where a 3A should be, you're probably OK for now, but you can buy 3A fuses, so just ask for one next time you're at your parts store.

 

Thanks "sofakingdom" and "Lurbie". Your help was much needed! Yeah i already ordered a 3amp fuse. Guess what they dont sell under 5amp in my place "Europe"..... go figure. I swapped all the other ones to the specs needed. Only the circuit breakers stay at 30amp (although the book says 35amp), but as "sofakingdom" explained, it doesnt matter, just trips at lower current if a malfunction happens. It hasnt happened yet so im good to go.

Thank you!