The heater in my Jeep suddenly stopped working. I thought it was probably the switch that was broken, so I decided to take it apart.
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I couldn’t reach it from the glove box side, so I’ll try removing the meter panel.
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I was able to safely remove the switch. That is a 30 year old!
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I tried using a electrical contact cleaner to see if it could be fixed, but it didn’t work.
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I also checked the fuse, and there was no problem there either.
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I thought the switch itself was at the end of its lifespan, so I ordered a new one. The product number is MA392880. Of course, it’s new and shiny!
I replaced the switch, but it still didn’t work, so I decided to check this next.
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The heater blower motor.
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I would like to remove the motor body, disassemble it and cleaning it.
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I had no idea what was causing the problem,
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but after further disassembly, it appeared that the motor brushes had reached the end of their service life. I measured the size of the brush and found that it was 6mm x 7mm, so I bought the one that was closest to the size at the hardware store.
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HiKOKI (former Hitachi Koki) part #999-041, size is approximately 6.5mm x 7.2mm. It was a little big, so I cut it down with a leutor to match the size.
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It fit perfectly, so I reassembled it and attached it to the Jeep.
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After connecting the wiring and temporarily assembling it to see if it would work properly, it worked fine! The cause was the motor brushes. It wasn’t a malfunction or anything, it was just a consumable item that needed to be replaced.
Brushless motors are convenient, but I thought it was great to be able to do something like this with an analog fix.
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