Maestro RR TPMS wiring issue heads-up and fix

For anyone who going to be doing a head unit retrofit, which requires a Maestro module and wiring harness to retain factory control and such, there is a minor issue with the wiring of the TPMS system. I ran into this problem with the install of a Pioneer DHM-WT8600NEX into my 2017 Tundra Platinum with the JBL system. I used the iDatalink Maestro RR interface module and the iDatalink HRN-RR-TO2 Factory integration adapter to do all the wiring. I bought everything through Crutchfield’s and install myself.

The issue is that with the new wiring kits do not properly wire the TPMS wiring so that the Maestro module won’t recognize the TPMS system in the truck. To fix this requires the installation of a 2K ohm resistor between the gray/red (TMPS lead) to the red accessory wire that runs between the head unit and the Maestro module. This requires a little soldering for a solid connection. After installing the resistor you then reset the Maestro module. Then the TPMS pops right up.

I got these instruction from a Maestro tech who was very familiar with the issue. I followed the instructions and all now works as it should.

You can buy the 2K ohm resistors on Amazon for dirt cheap.

Hope this is helpful to someone. Sorry, but didn’t take any pics but glad to help anyone else out who has this issue.

John

 

Are you referring to the TPMS showing up on the head unit or the dash display?

 

Showing up in the head unit, not the display.

 

Copy that. I did an install in my 2020 and did not have any issues. The TPMS goes through the data cable itself. You may have installed some cables that weren't needed which could have been the issue.....hard to tell without seeing it. Most of the cables that come with the Maestro are for a "one stop shop" type of kit.

 

Yeah, when I spoke with the Maestro tech he said it was a recent change in their harness that affects the Tundra. I thought I screwed up the wiring somewhere but it wasn’t my fault. Another issue is that it wasn’t clear on the RCA cable hook-ups from the wiring harness to the Head unit itself for the speakers. I didn’t realize that the JBL amp uses just the front channels to drive all the speakers in the truck. All sounds good but definitely not a Harman Kardon level of quality sound.

 

You still needed to connect to the OBD port correct?

 

No. The OBD data runs through that single data cable.

 

Does the RR2 have the same data cable? I'd love to not need the OBD2 connected in my '13 Sequoia.

 

Which one? The one in step 4?

 

The data cable is circled. I know that when I installed mine in my '20, everything runs through that single data cable. Not all of the cables in the kit are used. I have a picture posted in one of the threads showing which cables are not used.

 

On my 2017, this was the only remedy that worked (nothing else). I purchased the resistors for about $5.00 and placed it between the red/gray wire and the red wire coming running between the radio and Maestro unit. This got my tire pressure sensors to display on my unit.

EDGELEC 100pcs 2K ohm Resistor 1/4w (0.25 Watt) ±1% Tolerance Metal Film Fixed Resistor, Multiple Values of Resistance Optional

$6 EDGELEC 100pcs 2K ohm Resistor 1/4w (0.25 Watt) ±1% Tolerance Metal Film Fixed Resistor, Multiple Values of Resistance Optional

https://www.amazon.com/dp/B07HDDN1V8?_encoding=UTF8

 

And here I thought I had messed up something bad on my Pioneer install.. I’ll have to check into this fix. Thanks OP.

 

Thanks for the heads up…

 

Is this still working for you? I’m in the same boat. 2017, All other gauges work, even the ‘door open’ indicator works on Kenwood head unit but no TPMS or temp indicators. I’ve checked all connections and reset the Maestro with no success. Just to be clear, is the red wire you are referring to in the main harness? I can see the red/grey wire coming from the Maestro in the main harness and a like two-toned red wire in the harness as well, coming from the maestro. Is the resistor just soldered in between the two wires in that main harness?

 

I soldered the resistor between the red/gray wire to the red accessory wire (main harness). I believe the red/gray wire is also in the main harness. I recently disconnected my battery and had a hard time getting my TPMS to work. I had to reset the Maestro unit and on my head unit, when I go to the gauges, I have a car setting option and click on Validate PIDs. This seems to do the truck but it didn't this last time around when I disconnectedthe battery. I proceeded to use the Maestro OBD2 adapter (even though my idatalink cable was connected), did the steps (reset my Maestro and PID) and was able to get my TPMS to work. I would try validating the PID if you haven't already and verify you have an older main harness before you solder anything.

 

great, thanks a bunch for the reply and extra suggestions. I’ll try validating first. Funny enough, this all started when I switched out my battery a couple weeks ago. Maybe your fix will fix mine as well.

 

I have had TPMS working in my 2013 Sequoia with RR2 & Kenwood DDX9906XR for over a year, it stopped about a month ago and a reflash fixed it. Yesterday it stopped working and flash was a no go, it shows system not detected in diagnostics. I have resistors but really don't want to rip into my dash if there is another way. How does it work for a year if it needs the resistor?

 

Happily, there was a firmware update for the 9906 I missed last year and it fixed the TPMS. I still don't understand why it would just stop working.

 

I have the exact issue. I installed the jvc in January this year, tpms worked straight out of the box. Then about 3 wks ago all of a sudden it just quit one day. Reflash RR did nothing. All the wiring stays the same. Finally i did the resistor mod and it’s back up running again. So my thought was exactly like yours, why did it worked before and all of a sudden quit?
I could only speculate that the rr module must needed a certain voltage range to get the data and sometimes the voltage is out of that range and it won’t read it again. I dont know. Im just blowing smokes up my own azz perhaps. But, it’s working now. Oh yeah, i have 99 resistor leftover. Lol

 

Oh lord....I wonder if I will need the resistor eventually. It's been a year and a half or so lol.

 

Lol. You want one? I got spares.

 

I have a zillion resistors, I don't want to tear into my dash. It's otherwise working fine & my experience is don't mess with working wiring.

 

So I have a new twist. Pioneer 8600nex with rr unit. tpms works fine... except its rotated ‍♂️ as in the pressures all match-up with what my dash display reads (however appears to be more accurate, and will detect a pressure change quicker than the dash display) but the pressures are all "one to the left". If the image on the screen was rotated 90 degrees counterclockwise, it would be perfect.

I've tried reseting both the pioneer unit and the rr unit. Made sure both are running latest firmware. Refreshed the rr unit. Nothing.

I'd try flashing older firmware on the pioneer if I could even do that.

Platinum 2021 here.

Complete side note... does anyone have parking sensors, hvac or any of the other extras working (there are i think 3 or 4 grayed out icons below the gauges and tpms)? I figured at least the parking sensors would work because my truck has them...

 

Per Maestro: If you have an auto start on your vehicle, the auto start draws power not leaving enough power for your maestro to read the TPMS data.

The fix is to attach a 2k resistor from the grey/red wire from the maestro to the red wire on the maestro. So both wires stay intact but the resistor creates an "H" with the resistor being the horizontal part of the H.

I just pulled the sheathing away from each wire a little bit and soldered the resistor ends onto each respective wire. This gives the maestro the minimum power that it needs to read the TPMS data.

The tech did say that if your auto start just cranks and cranks and never starts after doing this modification, you may need to put in a relay to "disconnect" the red wire from the grey/red wire which would give the auto start the power that IT needs until the vehicle starts, then it would connect giving the Maestro grey/red wire the power it needs from the red wire.

 

I do have remotes start on my truck. The resistor trick fixed my tpms issue. Haven’t had any problem since the mod.

 

I don't have auto start nor remote start and my tpms worked for one day and never again. I'm too lazy to pull apart the dash right now to play around with it right now. It was a PITA to fit all the wires and module in the back, very little room to store everything!

 

Just came across your post.
Ran into this with my pioneer and finally figured out why.

Standard order for scanning sensors is LF, RF, RR, LR. Thus they are loaded into the TPMS ecm that way. The problem was that the first sensor is assigned to LF, but then second is assigned to LR, third to RF, fourth RR.
After some looking I found that Maestro is aware this can happen. Other variations can happen based on how the head unit displays the image.

So there is a menu in the tool option to remap the posiitons. It will initiate an interactive process that tells you to lower the pressure in the LF tire, when it senses the drop it blows the horn. You repeat the process by following the screen prompts until all four tires are mapped.

 

Anyone with 99 resistors want to toss a couple in the mail. Seems like a waste to purchase 100 of them Let me know. My TPMS will work sometimes but then will just be gone and nothing I can do to get it to show again. Figured I can try the resistor setup.

Thanks, Mike

 

Yeah man. Let me find an envelope. PM me your address and I’ll get you some.

 

I lost my TPMS again, reset the RR2, reset the 1057, added the 2k resistor between red/red grey. NO TPMS.

Called ADS, the lack of giving a damn was palpable, I thought Canadians were nice?

They blamed my remote start that is between my OBD2 & the port, I tried without the remote start no change. Anyone find a solution?