Trailer TPMS sensors loose signal

[DNHMIKE]

I just picked up my trailer from storage today, TPMS were installed last fall on the trailer and worked fine. No reading from them, I drove 10 miles and still no reading, I used the relearn tool and all 4 TPMS were able to be read by the truck (truck running the whole time), I drove 2 hours and pulled over to take a break, I turned the truck off, got out and walked around for 10 minutes, got back in the truck, started it up and NO readings again, NO SENSORS found? what gives? You buy a $70,000. dollar truck for this crap?

 

HELP PLEASE..

[Gecko50]

On 3/2/2021 at 9:52 AM, L8T said:

I don’t think you can run 2 receivers without reprogramming the module that controls them to understand it’s splitting the signals going to it and you may even have to run two different frequencies due to overlap. You could have for instance the rear truck axle being picked up on both the truck and trailer receivers sending it twice. The way the system is currently designed you can only run one at a time. 
 

I never thought about losing signal from the steer axle if you moved the receiver back. This could definitely pose a problem. Unless reading the trailer is more important than the truck. Ideally, a signal booster or repeater would be the best option to install on your trailer and leave the factory TPMS receiver where it is. 
 

FWIW we have a low bed at work that is 125’ long and it has sensors and brake controls on the rear axle that operate via canbus. The module on the trailer has its own power wire outside of the twisted pair and all the twisted pair does is carry the ground, can-hi and can-low signals. Most can networks are designed to work this way. 

L8T, so I was thinking I have my 48 foot trailer as noted above. Thinking of the factory TMPS receiver conflict with the one that is located behind the rear truck plate. I have enough distance to place the second TMPS (new) receiver to the rearward of all three axles. This is a lot further than 23 feet. It would be parallel the factory one and I would think its not a conflicting signal no programing would be needed? The main problem I may encounter is the longer cable length of the twisted pair. I could tap into my 12 volt on board trailer power so only the twisted pair would be a sole cable also reducing the interference of the 12 volt power. What's your thought?

 

Chuck

[L8T]

Although there may be a way to physically tie in the second receiver, when hooked to the network the can bus protocol can be disrupted by adding another device to the circuit without the other controllers or ecm/bcm knowing its there or that it should even be looking for it. This can cause the other controllers or the ecm/bcm to not understand what’s going on and just fault out.

 

If the provision is already there to add another receiver then it is no issue. Not sure this is the case in this instance. 
Attached is a pic of a simple can bus network showing how the controllers connect and the resistors. Not shown is the ecm/or bcm that logs, stores and converts the data shared between the controllers and itself.

[Mbower2020]

To Gecko50 and everyone else working this problem.   Made my extension harness and just gave it a run here is what I know.

 

The Trailer TPMS module is a stand alone system.  Proved this by hooking up my autoenginuity scanner.  I have had the module unplugged since I posted the photos with no impact to my vehicle TPMS signals all 4 working fine.  Before I started this process today I looked for the module in the software and it said it could not be found.  I then plugged in my newly made 30' extension rescanned and the module appeared with no issues.  So I thought ok we are on the right track.   When I placed the module closer to the trailer wheels I was about 10 or 12 ft away I was able to activate the sensors with my tool (I was parked and not moving they were dormant at the time) and they all came in the first try.   I have not taken it out on the road yet but I am anticipating that we got it licked. 

 

One important thing you have to face the module in the direction of the wheels as it was facing behind the license plate.  

 

 

[Gecko50]

4 hours ago, Mbower2020 said:

To Gecko50 and everyone else working this problem.   Made my extension harness and just gave it a run here is what I know.

 

The Trailer TPMS module is a stand alone system.  Proved this by hooking up my autoenginuity scanner.  I have had the module unplugged since I posted the photos with no impact to my vehicle TPMS signals all 4 working fine.  Before I started this process today I looked for the module in the software and it said it could not be found.  I then plugged in my newly made 30' extension rescanned and the module appeared with no issues.  So I thought ok we are on the right track.   When I placed the module closer to the trailer wheels I was about 10 or 12 ft away I was able to activate the sensors with my tool (I was parked and not moving they were dormant at the time) and they all came in the first try.   I have not taken it out on the road yet but I am anticipating that we got it licked. 

 

One important thing you have to face the module in the direction of the wheels as it was facing behind the license plate.  

 

 

I am curious as to what are the front wheels reporting to the receiver? What is the new distance from  the front wheels from the original rear license plate location of the receiver and the new location of the receiver on the trailer. Does it still pick up the TMPS front wheel signals, this would require a road trip on your trailer / truck. Where are you picking up power from (+ / - ) are you using the trailer power or the original power or using the trailer power? Have you made up a new jumper harness with the same connectors, or solder and splice to extend the factory harness to the receiver? I just got my connectors from Amazon for the factory TMPS receiver.

 

Thanks 

 

Chuck

sorry for all the questions.

 

[Gecko50]

8 hours ago, Mbower2020 said:

To Gecko50 and everyone else working this problem.   Made my extension harness and just gave it a run here is what I know.

 

The Trailer TPMS module is a stand alone system.  Proved this by hooking up my autoenginuity scanner.  I have had the module unplugged since I posted the photos with no impact to my vehicle TPMS signals all 4 working fine.  Before I started this process today I looked for the module in the software and it said it could not be found.  I then plugged in my newly made 30' extension rescanned and the module appeared with no issues.  So I thought ok we are on the right track.   When I placed the module closer to the trailer wheels I was about 10 or 12 ft away I was able to activate the sensors with my tool (I was parked and not moving they were dormant at the time) and they all came in the first try.   I have not taken it out on the road yet but I am anticipating that we got it licked. 

 

One important thing you have to face the module in the direction of the wheels as it was facing behind the license plate.  

 

 

Ok reread your post above at least 10 times and broke it down. So you are saying that the main truck tires 4 or 6 tires appear to have its own TMPS receiver elsewhere on the truck. I also understand that the TMPS receiver that is located in back of the license plate is sole use is the trailer tires? So I am now curious just how long the extension can be made without affecting the CANN BUSS. You made a length of 30 feet, how much longer do you think it can be made? CN you attempt to make it 50 feet and if problems occur maybe 40 feet? I also understand that the orientation of the TMPS must be maintained. Now on your extension cable did you use an twisted pair only for signal and utilize straight wire for power? This IS a great start of resolving our TMPS issues. 

 

Chuck

[Mbower2020]

Gecko50, you are correct on your last quote.  The truck has another module just for the vehicles wheels where it is I have no idea.  I have been driving around about a month without the receiver plugged in.  Its been sitting on my work bench since I posted the photos.  No issues with vehicle TPMS I have actually seen pressures change.   As for the cable I just have a straight up extension.  I simply plugged in my male/female extension where the Trailer TPMS receiver resided using same power source that powered the receiver.  I think we should be able to go 50' no problem.  Remember we just need to keep the module within 20' of the furthest tire from the receiver.  I plan on mounting my receiver on a bracket under my 5th wheel.   As for wire I used 22ga twisted shielded for the CAN/BUS and 20ga speaker wire for the power.  Stuck both in a non-slitted wire loom I bought off of Amazon.  

[Mbower2020]

Here are some pics.

[Gecko50]

13 hours ago, Mbower2020 said:

Here are some pics.

This is music to my ears. But the final question is that can you run the truck without a trailer TMPS receiver? and how will that effect the on board systems with missing TMPS trailer receiver? will it generate codes. Also IF I was to permeant install a new TMPS under my trailer and make up a cable to my truck with a built in connector in the bed. Then I would have to disconnect the TMPS under the license plate? The reason I want to not remove any wiring or plugs to hook my trailer under the truck or license plate. A simple means but it would either mean removing the existing TMPS receiver leaving it out when not towing OR having a way to disable the on board receiver on the truck. Just trying to think of a easy way to tow. The last real question is that can you just install a new TMPS receiver and not require a dealer to program or code a new receiver for the trailer, even if you have 1 in operation at a time. basic can one run without receiver and or buy a new receiver and swap operation at a time to tow? will the change create problems?

 

Chuck 

[Andrew Best]

FYI regarding the main receiver;

I was told by my service manager that the receiver for the trucks sensors is in the left rear upper cab pillar. I am having trouble with mine loosing communication with the right front sensor. They replaced the sensor with no improvement. They claim it is due to interference from my iPhone and other electronics i have plugged into the dash as well as it being the furthest from the receiver.. However it drops it with everything unplugged also.

[Gecko50]

2 hours ago, Andrew Best said:

FYI regarding the main receiver;

I was told by my service manager that the receiver for the trucks sensors is in the left rear upper cab pillar. I am having trouble with mine loosing communication with the right front sensor. They replaced the sensor with no improvement. They claim it is due to interference from my iPhone and other electronics i have plugged into the dash as well as it being the furthest from the receiver.. However it drops it with everything unplugged also.

If by chance the next time in service for the receiver maybe grab a photo of that part. would be nice.

 

Thanks 

 

Chuck

[Mbower2020]

Ok, Andrew thanks for that information.  Chuck to answer your questions I have been running my truck without the module for about a month will no codes and no ill affects on any other system on the truck that I have noticed.  For me I just have the one trailer for now that I will be monitoring so I am going to leave the module with the trailer.  If perhaps I decide to put sensors in my gooseneck I would have the wiring in place and just move the module.  Which leads me to the question you asked about multiple modules.  I do not think you can have 2 modules even if you use one at a time.  They have to be programmed to the system (learned).  They also store all of the TPMS sensor ID's.  For multiple trailers if you have more than one programmed on your app.  Right now I am assuming this by putting 2 & 2 together scanning through my OBD2 software looking at what functions I am given.  I have attached some screenshots of what I was looking at.  First one no codes present with module out of truck, second functions I was able to get into by accessing TPMS module actuations on my autoenginuity software, third dashboard TPMS screen for vehicle functional with no issues.  

 

Mike

DTC Screen 2020 GMC 3500 No Trailer TPMS module installed.pdf TPMS Module commands.pdf

[Gecko50]

2 minutes ago, Mbower2020 said:

Ok, Andrew thanks for that information.  Chuck to answer your questions I have been running my truck without the module for about a month will no codes and no ill affects on any other system on the truck that I have noticed.  For me I just have the one trailer for now that I will be monitoring so I am going to leave the module with the trailer.  If perhaps I decide to put sensors in my gooseneck I would have the wiring in place and just move the module.  Which leads me to the question you asked about multiple modules.  I do not think you can have 2 modules even if you use one at a time.  They have to be programmed to the system (learned).  They also store all of the TPMS sensor ID's.  For multiple trailers if you have more than one programmed on your app.  Right now I am assuming this by putting 2 & 2 together scanning through my OBD2 software looking at what functions I am given.  I have attached some screenshots of what I was looking at.  First one no codes present with module out of truck, second functions I was able to get into by accessing TPMS module actuations on my autoenginuity software, third dashboard TPMS screen for vehicle functional with no issues.  

 

Mike

DTC Screen 2020 GMC 3500 No Trailer TPMS module installed.pdf 326.16 kB · 1 download TPMS Module commands.pdf 303.77 kB · 0 downloads

Ok this is great info. I will be moving my trailer TMPS receiver very soon. 

 

Thanks

 

Chuck

[Gecko50]

15 hours ago, Mbower2020 said:

Ok, Andrew thanks for that information.  Chuck to answer your questions I have been running my truck without the module for about a month will no codes and no ill affects on any other system on the truck that I have noticed.  For me I just have the one trailer for now that I will be monitoring so I am going to leave the module with the trailer.  If perhaps I decide to put sensors in my gooseneck I would have the wiring in place and just move the module.  Which leads me to the question you asked about multiple modules.  I do not think you can have 2 modules even if you use one at a time.  They have to be programmed to the system (learned).  They also store all of the TPMS sensor ID's.  For multiple trailers if you have more than one programmed on your app.  Right now I am assuming this by putting 2 & 2 together scanning through my OBD2 software looking at what functions I am given.  I have attached some screenshots of what I was looking at.  First one no codes present with module out of truck, second functions I was able to get into by accessing TPMS module actuations on my autoenginuity software, third dashboard TPMS screen for vehicle functional with no issues.  

 

Mike

DTC Screen 2020 GMC 3500 No Trailer TPMS module installed.pdf 326.16 kB · 4 downloads TPMS Module commands.pdf 303.77 kB · 2 downloads

Good morning Mike. I was wondering did you or will you use a twisted shielded cable for the TMPS signal conductor. If you used a shielded wire normally its grounded at the supply / source end. Are you grounding the shielded wire or are you just using twisted shielded cable.

 

Thanks

 

Chuck

[ShogunKC]

The Trailer TPMS module is a stand alone system.  Proved this by hooking up my autoenginuity scanner. 

 

Tell me about your Autoenginuity Scanner - can it read and send CAN BUS commands/signals?

 

I want to control the behavior of the parking lights and understand that they are controlled through the BCM. My OBD scanner doesn’t do much (ie it’s cheap).