Dash air blower overheating fuse on high

[HarveyP]

My blower for dash air and heat/vent is overheating the fuse leading to the blower relay. I replaced the fuse holder and wire to the relay with a #10 gauge wire and fuse holder. The amp draw is 11.5 amps. Fused with a 15 amp fuse, the fuse does not blow, but gets hot enough to deform the plastic of the fuse. On settings lower than high, the fuse and wire stay cool, but the fan speed switch handle gets hot. I replaced the blower motor with a Napa replacement, but the problem did not end. Any thoughts? I know we have some very bright and experienced people on this forum. Thanks, HarveyP

[WRENCH18]

Originally Posted by HarveyP

My blower for dash air and heat/vent is overheating the fuse leading to the blower relay. I replaced the fuse holder and wire to the relay with a #10 gauge wire and fuse holder. The amp draw is 11.5 amps. Fused with a 15 amp fuse, the fuse does not blow, but gets hot enough to deform the plastic of the fuse. On settings lower than high, the fuse and wire stay cool, but the fan speed switch handle gets hot. I replaced the blower motor with a Napa replacement, but the problem did not end. Any thoughts? I know we have some very bright and experienced people on this forum. Thanks, HarveyP

dodge had the same problem in the mid 90.They installed a overlay harness wich contained a relay and bigger wires to move the amp draw away from the sw and smaller wires to the new harness with larger componets.Also note if you have a 15 amp circuit it should never be more than7.5 amps,that is how they are designed.if you are seeing 11 there is some resistance building up in the old wiring bad motor,which you replaced,bad sw ,bad wiring. I would have the blower system rewired with at least 12 to 10 ga wire. in the heat blower motors will pull a lot of amps.As load increases so does amp draw,heat creates resistance. Global warming!