Bench demo of the inline PTC fuse. The under-dash job does not leave enough room to show the splice, so this is the failed heater on the table: how the 25A holder actually connects. This is the follow-up to the in-car PTC heater video. Same connections on Gen 1 and Gen 3. FSD Model S and Model X use the same refresh/Gen 3 heaters. The unit in the previous Model S video was the older Gen 1 style. Terminals are the same either way. KIT — FUSE, HOLDER, CRIMPS 25A semiconductor fuse, holder, and the crimp style shown. Holders and fuses have been hard to source. ebay.us/rwkuWg WHAT YOU ARE LOOKING AT • Failed PTC from a Model X that already took out the 400V fuse • Three connections: negative, positive, ground • The ground is a conductor inside the sheathing, like coax. Outer shield/ground, inner power core • Strip the outer jacket, peel it back, strip the conductor, crimp both ends. Crimps make a cleaner joint than a bare twist • Fuse the positive. You can fuse the negative, but positive is the usual choice • Do not fuse both wires. That forces you to bridge the ground conductor. Fuse one side and the ground path stays intact back to the junction-box plug and forward to the heater • Boot still seals moisture. Holder with the 25A fuse sits next to the heater and slides back into the housing • Control connector and the orange cable stay fished through the firewall. You are only cutting the PTC feed at the heater SAFETY This is ~400V DC. DC does not let go. Power the car down, pull the fireman’s loop, disconnect the 12V battery, and wait. Do not cut or touch bare PTC wires until the car is dead. Insulated gloves. If you are only swapping the heater core, same rules. Stock is limited while these get sourced. Link is in the description. #Tesla #ModelS #ModelX #PTCHeater #TeslaRepair

Legacy Model S and Model X PTC heater failure, the 400V fuse that blows, and a $45 inline fuse so you do not have to drop the high-voltage battery. Also covers blower removal and brush replacement. This is for pre-refresh legacy cars with the vertical screen. Model S and Model X, 2021 and earlier. Gen 1 PTC shown. Refresh-front cars use a similar Gen 3 unit with the connector more in the middle. A small number of early Model 3s had a PTC before the heat pump. This job is the S/X layout. HVAC Blower Repair companion video: youtu.be/oxNozxwB0hw WHY THE HEATER DIES • PTC heaters have a finite number of power cycles • IGBTs (the electronic gates that switch the elements) wear out and can fail shorted on or off • A heating element can also short • Either one blows the ~40 amp / 400V fuse in the high-voltage junction box under the hood • That fuse is about $45. Tesla labor to replace it runs roughly $650–$1,000 FUSE LOCATION • Model X: reachable without dropping the battery, but not fun. Wipers and air suspension out of the way, then fish a hand between the drive unit and the cover. Plan 3–6 hours • Model S: junction box faces the firewall. Cover comes off toward the firewall. Blind work in a 400V box. Most people end up dropping the pack • Very early Model S: box can sit behind the wheel well and is reachable on a rear-drive car. Dual motor, forget it THE FIX IN THIS VIDEO • Leave the 40A fuse in the DC junction box • Cut one PTC feed and add a 25A semiconductor fuse in a holder right next to the heater • Full-power PTC draw is about 18 amps, so 25A has headroom and should open before the buried 40A on a hard short • Proactive PTC swap at 200,000+ miles. Original still worked. Old unit kept as a spare. These are getting hard to find • HVAC blower drops out on three screws. Brushes were near end of life after ~5 years / 150,000 miles. Spring no longer pushes hard enough • Brush sets: $10 shipped, pre-ground to the commutator curve. Tesla blower job is a few hundred dollars WHAT COMES APART • Piano-black dash trim. Obeche wood going back on this car. Pulling this is not 100% necessary on most cars. If it is an FSD Model S, it may be • Glove box. T20s, light, latch, open/close sensor • Passenger airbag module moved aside (10mm). On the Model S you do not have to unplug it. If you are nervous: power down, pull the fireman’s loop • Carpet, plastic shield, diverter (outside air vs recirculation from the corner of the dash) • Orange corrugated 400V tube down to the PTC • Heater held by three screws. HV lugs disconnected at the heater instead of fishing the orange cable back through the firewall SAFETY This is 350–400V DC. DC does not let go. Power the car down from the screen, pull the fireman’s loop, disconnect the 12V battery, and wait. Tesla says 2–3 minutes. I wait 10–15. Do not cut or splice the PTC wires until the car is dead. If you are not comfortable in a high-voltage box, do not do the buried fuse by hand. ALSO IN THE VIDEO • Green HVAC fan-speed resistor • Good time to foam-clean the evaporator if the cabin smells • 2017 refresh with the biohazard filter: FSD computer sits right there and uses recirculation to pull heat off it • Follow-up on blower brush replacement, bushing lube, and cleanup Legacy S/X, vertical screen, no heat or weak heat. Start here before you pay to drop the battery for a fuse. #Tesla #ModelS #ModelX #PTCHeater #TeslaRepair

Legacy Model S and Model X HVAC blower on the bench: the two things that actually wear out, how to replace the brushes, and how to oil the bushings so you do not buy a $200 fan. Follow-up to the PTC heater video: youtu.be/Mmfyri1m5sA Once the glove box and airbag are out, the blower drops on three screws. This clip is the motor itself. Bosch, made in Korea. Failure points and the rebuild. BRUSHES — $12 SHIPPED, PRE-GROUND / ANGLED Two brushes, solder or crimp ready, ground for the Tesla commutator. It sits slightly off-center, not like a typical GM motor. ebay.us/ylRWCj FAILURE POINT 1 — BRUSHES • Two graphite brushes in channels, each pushed by a spring onto the commutator • As the brush wears, spring tension drops until it cannot keep contact • Stretching the old spring buys maybe a year, then you are back in the dash • Snip the pigtail as close to the old brush as you can and solder the new one to the existing wire • Wire has to slide freely in the channel as the brush wears. Do not let the joint touch the case • Replacements are a bit longer than factory. Bosch used a copper-graphite mix. These are graphite and have been lasting about the same • Blow the dust out with compressed air or canned air before you close it. Brush dust is conductive graphite FAILURE POINT 2 — BUSHINGS, NOT BEARINGS • Two self-lubricating bushings. The lube wears out • Use 3-in-1 / hobbyist electric-motor oil. Not engine oil • Wipe the bushing, a drop, spin it, another drop, let it soak. Do not flood it • Top bushing is open. Bottom one: pry the C-clip with a flat screwdriver while you hold it so it does not launch, pad the fan, tap the shaft out gently, oil the inner bushing, reinstall the clip • Motor can come out of the housing for a better blow-out • Wash the fan and the plastic. Do not wash the motor. Let it dry fully First time is about half an hour. Soldering the pigtail is the annoying part. A crimp works if solder will not wet. Spare blower on the shelf means the next no-air complaint is a swap, not a dash teardown. #Tesla #ModelS #ModelX #HVAC #TeslaRepair

So I managed to outsmart SUPERGROK on a game of 20 questions so bad I hit Paid Grok usage limits! I've tried to hit the limit in the past but could never come close! @grok @elonmusk @xai

I see, i'm just a lowly supergrok subscriber.

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