02LS1Z28BC

iTrader: (4)

01ss HUH?

sparky, did you feel the top of that 30 amp fuse? Do you have any broken filaments on your grid? Have you Ohm'd out your grid with one of the wires disconnected, not all grids are the same, and you do not want any other circuit before the 'connected' grid influencing your reading. Just disconnecting one side of the grid (either side) will totally isolate the grid for measuring its resistance. Have you put an inline ammeter in place of the fuse and started your vehicle and turned on the defogger therby measuring the current draw through that circuit? You cannot have an accurate measurement of the normal operating current or voltages with the car not running because the battery voltage is much much lower and the current drawn will be less than when the car is running (and) the defogger normally is used when the vehicle is driving down the road, as designed. It also isn't a good idea to run the defogger before the car is started, the @ 10 minute timeout is a long time for a battery to be running, especially if it is a year or more after purchase. The defogger is meant to be turned on while the vehicle is running. In my case, the 35.6 amps through that 30 amp fuse (at 14.24 volts) made the thing blistering hot after a very short while. Some grids are a higher internal resistance, some are not. If the grid is of a higher resistance (calculated) minimum, that would result in a lower current and no overheating problem on either the OEM 30 amp breaker, or a 30 amp fuse. Every car is different, and if they didn't factor that in when they built them, it is a design flaw. I seriousely wonder how many F bodies burned up because of this 'fix' of just inserting a 30 amp fuse. The safety device for the extreme of at least my vehicle as built, is a 35 amp safety device. The only 35 amp safety device I can locate that will maintain its form and function, is that 35 amp fuse. I cannot locate a 35 amp designed circuit breaker for that position in the panel. I can wire one in but the resulting connectors/wiring/co-located 35 amp terminalized breaker is just too much to mess with given the space provided and the clearances of the panel/cover. A 0.6 amp measured (over the rated 35 amp fuse) is well within a conservative 10% design variable so I have no problem using that as this circuits safety device. GM may or may not know about this, I know it would have been VERY expensive to have the GM engineers any fix to this problem. I also know the wiring in this circuit will handle 36 amps continuous without a overheating problem as well, so the safety device (35 amp fuse) will work. It will also 'pop' if the downward leg of that hot lead to the grid shorts, as it would being a fuse or a breaker in that position. A serious word of caution. THERE ARE 40 AMP fuses commonly in these auto stores that will fit. JUST REMEMBER putting one of those in there will result in a 33.33% increase in the designed safety factor that was built in, and it is dangerous to go above @ 16% of its original design, as a general rule, without doing a lot of homework that I have already done. I also need to point out, this proceedure works only if everything else in the circuit is working PROPERLY. All these readings are based on the values at each device as tested with all connections tight and in good repair IN MY CAR. Test everything before you change anything, use good equipment, and find out where they should be connected to make sure its right.