TraviZ06

I have an 02 Z. With this hot cali weather lately I noticed my car getting hot in traffic. I came home one night and popped my hood to notice only one of my fans (drivers side) is running. My passenger fan was not moving. I can freely spin it by hand. I checked my fuses under the hood and my 30amp maxi fuse #46 I think, is blown. I put a new one in, drove it a day, checked that night and it was blown again. I thought maybe my fan motor is bad so I ordered a new one. While waiting for delivery, I went under my car and unplugged my fan motor on the passenger side and put another new 30amp fuse in.
I just went for a drive and came back and the fuse is popped again without the fan even being plugged in. I doubt it is the motor at this point. What else can I look at that would cause this fuse to keep blowing?

73Corvette

Normally a short pops fuses...

TraviZ06

Yes sir. With the fan motor eliminated from being the short, what else between the fuse and the fan exists that could cause this?

TraviZ06

Thanks for the schematic. Since I see fuse 46 runs through relay 43 and 44, I swapped relay 43 for relay 45 since they have no crossover. Both fans worked when tested with hptuners VCM scanner to force them on. They also both worked with relay 44 completely removed . I am not sure the function of relay 44. Either way, both fans were working when I switched out relay 43 and 45. I put them back and both fans still worked. I put back in relay 44 and both fans still worked. After about 2 minutes of engine idling with both fans on, i hear a pop and the fuse 46 went dead again.

This tells me its not a constant short but a possible heat-related one since it is also 109 degrees here in cali right now.

I think I will replace all three relays and of course the dead fuse again for one more test. If the fuse still pops, I will go ahead and replace the motor. Maybe the heat is making it draw too much current.

Unless you guys have any further suggestions?
BTW, thanks for taking the time to read and hopefully understand this post!

73Corvette

So what role does #46 play... and why does it keep popping?

TraviZ06

Thank you. Let me elaborate, Ac was off for these tests I did. Also, my tune has been modified to allow low speed on at 175 and high speed on at 180. Both turn off at 160. I did use hptuners with ignition on to force low mode which only activated the drivers fan. This tells me that the relay 44 may not be switching properly

TraviZ06

I'm thinking relay 44 may be internally grounded, hence why no power is making it to fan#2 and also the current from fuse 46 traveling into relay 44 is possibly going straight to ground.