Apparently I wasn't clear... I don't need help with this, this was informative only. I know why it melted, and I was letting everyone know what resistance is used in the napa adapter harness. It is only a 1/4 watt resistor.
So, to sum up, if you want to use a junkyard connector when swapping to a CS style alt, you don't need a large wattage resistor, but you do need a resistor for sure and it needs to be adequately supported. Just covering it in heat shrink is not enough. And the NAPA part uses a 500 ohm resistor.
I have seen several questions on the board in regard to SI10/12 to CS130 conversions. Here is some additional info. Apparently the resistor is required when you don't have a warning light.
I am in the midst of rewiring my Blazer and found something alarming. This wire was melted through the insulation in the main bundle in the cab. Luckily it was still wrapped in the insulating tape and hadn't melted any other wires
The wire shown is the control wire to the alternator from the ignition switch on my stock harness. I converted to a CS130 in the fall of 2007, and included a resistor inline to the "L" terminal on the CS130. Apparently I didn't properly support the resistor on the wire. I was driving out of town and noticed that my alt wasn't charging, so I pulled over and found (after some time troubleshooting) that the resistor lead had broken at the resistor body. So, as I didn't have a spare resistor or soldering iron with me, I just removed the resistor and reconnected to wire to the "L" terminal directly to the control (brown) wire.
I never got back in and installed a new resistor after I got back home as it seemed to be working fine. Well, apparently the resistor is merely there to limit current in the wire to a reasonable amount.
The Napa adapter mentioned in several other posts includes a 500 ohm resistor inline to the "L" terminal.
So, to sum up, if you want to use a junkyard connector when swapping to a CS style alt, you don't need a large wattage resistor, but you do need a resistor for sure and it needs to be adequately supported. Just covering it in heat shrink is not enough. And the NAPA part uses a 500 ohm resistor.
I have seen several questions on the board in regard to SI10/12 to CS130 conversions. Here is some additional info. Apparently the resistor is required when you don't have a warning light.
I am in the midst of rewiring my Blazer and found something alarming. This wire was melted through the insulation in the main bundle in the cab. Luckily it was still wrapped in the insulating tape and hadn't melted any other wires
The wire shown is the control wire to the alternator from the ignition switch on my stock harness. I converted to a CS130 in the fall of 2007, and included a resistor inline to the "L" terminal on the CS130. Apparently I didn't properly support the resistor on the wire. I was driving out of town and noticed that my alt wasn't charging, so I pulled over and found (after some time troubleshooting) that the resistor lead had broken at the resistor body. So, as I didn't have a spare resistor or soldering iron with me, I just removed the resistor and reconnected to wire to the "L" terminal directly to the control (brown) wire.
I never got back in and installed a new resistor after I got back home as it seemed to be working fine. Well, apparently the resistor is merely there to limit current in the wire to a reasonable amount.
The Napa adapter mentioned in several other posts includes a 500 ohm resistor inline to the "L" terminal.
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