Disconnecting TPMS receiver to stop warning light?

[Ohio Enthusiast]

Is it possible to stop the TPMS warning light when not using TPMS sensors in the wheels by disconnecting the TPMS receiver module (applies to aftermarket wheels and multiple wheel/tire sets)?
I read in some other forums about the potential to stop the warning light if you disconnect the receiver when the light is off (i.e. disconnect it when the stock wheels with the TPMS are still on the car). Has anyone ever tried that? I don't care for the TPMS, and getting a summer wheel/tire set would be nice not to have the warning light on. If it was a quick access I would have tried it, but removing the rear shelf looks like a real PITA.

It looks like the receiver is 88831CA030 and is shared with the keyless entry (which luckily I don't have). It appears to be under the rear shelf cover.

From here:

SKU: 88831CA030
Other Names: Keyless Entry Receiver, Tire Pressure Monitoring System Receiver, Receiver Ay(S T) US
Description: BRZ. With keyless ignition. Keyless Entry Receiver.

The Toyota service portal has this under Suspension/Tire Pressure Monitoring/Tire Pressure Warning Receiver. It's called "DOOR CONTROL RECEIVER" there.

You can see the receiver in the last picture of the post about removing the rear shelf - the black box with the white label just right of the upper Latch connector.

I tried following the wiring diagram to find a more convenient location to disconnect this, but couldn't make heads or tails of it. Does somebody know how to find the other end of this connector? I think it's HD1, but that's also shared with a ton of other stuff. I suppose I can try disconnecting just the receiver wires from that connector...

I also tried pulling fuses, but the most promising one (main fuse #27 - Keyless access with push button start system) is missing in my car (since I don't have keyless access) and the other two (main fuse #48 - Remote keyless entry system, main body ECU and main fuse #33 - Automatic air conditioning system, gauge and meters (based on the wiring diagram)) stopped my key fob from working (which I still want), but also stopped the TPMS light from lighting up on startup, which I guess is a good sign. This also leads me to suspect that the receiver might also handle the non-keyless entry key fob, which would suck big time to discover only after removing the rear shelf...

[churchx]

If you try fiddling with it, also check if change 'sticks' with eg. battery disconnects.
Among other means to shut TPMS warning off (apart from tape over indicator, lol) imho might be mini-airtank to screw all four sensors in, pump to some pressure and bring along in car, or trac-box that IIRC also can disable TPMS via canbus, not just fan control and pedaldance.

[Ohio Enthusiast]

Originally Posted by churchx

trac-box that IIRC also can disable TPMS via canbus, not just fan control and pedaldance.

That's interesting, thanks! I wonder if I could DIY something with an Arduino (I saw some for locking above speed), since it's pretty pricey.

[LimitedSlip]

Not too many places to unplug the receiver:

[Ohio Enthusiast]

Originally Posted by LimitedSlip

Not too many places to unplug the receiver:

Awesome, thanks for the annotations! I saw the diagrams, but it didn't really add up. You helped a lot, I'll see how easy it would be to yank the wires from the connector (might be difficult, seeing as it's a multiple rows connector).

[churchx]

And maybe not yank, but put extra switch on that wire?

[LimitedSlip]

At least the three pins in question are in an outside row:

[ZDan]

I just leave light on as reminder to check pressures regularly...

[Ohio Enthusiast]

Originally Posted by churchx

And maybe not yank, but put extra switch on that wire?

Sure, for a permanent solution, but for a quick test it should be possible to pull the wire lead from the connector (typically there's a small tab on the lead that you can depress with a thin pair of tweezers - I have one for sub-0402 components, hopefully would be thin enough).

Originally Posted by LimitedSlip

At least the three pins in question are in an outside row:

Fingers crossed that it'll work, thanks! I'll try it out in the evening.

[Busybee]

I don’t want to be rude but is there something that I am missing?
Why not putting new sensors which is safety issue. Is it that expensive?


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[Ohio Enthusiast]

Originally Posted by Busybee

I don’t want to be rude but is there something that I am missing?
Why not putting new sensors which is safety issue. Is it that expensive?


Sent from my iPhone using Tapatalk

It's hardly a safety issue. It's not even the case of seatbelts or ABS where people always say "we managed for decades without it". It's more like an electronic oil level gauge - a decently aware owner would have no need for it, since he checks the tire pressure (or oil level) regularly. The only situation where a TPMS sensor will actually alert you is a sudden large pressure drop, one that would be easily felt by the driver anyway. Any slow leaks (either natural pressure drop or a slow puncture) will be caught by an attentive owner.

As for the reason, yes, cost - paying $200-$250 (sensors and scanner) to satisfy a feature I don't need is something I don't care to do. Obviously I could live with the light, but I was curious if I could find a free way to disable it (other than covering the light in the dash).

[LimitedSlip]

Originally Posted by Busybee

I don’t want to be rude but is there something that I am missing?
Why not putting new sensors which is safety issue. Is it that expensive

OEM part is $100-125 per wheel:

https://www.sparksparts.com/oem-part...g0LWdhcw%3D%3D

[ls1ac]

I think that you will find this is a combined buss communication system and disconnecting one wire will stop several different communications from happening.

[Ohio Enthusiast]

Well, I tried fiddling with the HD1 connector, but it's way too cramped in there for such delicate work without some additional disassembly of the wiring loom. Combine that with my growing suspicion that the TPMS receiver is indeed a part of the key fob remote receiver and disabling one will disable both.

I'll try to see if I can find a CAN command to disable the light or the TPMS entirely, and if that fails I'll just cover the light in the dash.