Nuvi and TPMS Interference

[totalboard]

I am having problems with the display on my Nuvi 765 interfering with the TPMS system on my
Honda CRV. I have had the car in the service department four times and the error codes on the
TPMS are always the same. The last time they showed me an article on RF interference with the
TPMS and it included DVD monitors and cell phones. A Ford engineer wrote an article http://www.underhoodservice.com/Article/40032/dispelling_tpms_myths.aspx about continuous
RF interference and that seems to be the problem I am having. I will drive about 15 or 20 miles
on the highway with my Nuvi on and the TPMS light will come on. I will turn off the Nuvi and
seconds later the system light will go out. I have tried it without the Bluetooth on and it still comes
on with the display on. I have tried other outlets in the car and moved the display around on the
dash but I get the same results.
Has anyone else noticed this on Honda or other makes of automobiles and do you know if there
is a way to filter the EMI coming from the Nuvi? Honda doesn't seem to see it as their problem.

[gatorguy]

Thanks for bringing that study to our attention. We've had an occasional post concerning the issue you've mentioned, but little background or evidence to look at.

[kingmeow]

Hmm, interesting! I have a new '09 Acura TL SH-AWD (Honda product) and my Nuvi 260 does not interfere with the TPMS. What kind of TMPS does your CRV have? Are there sensors in the tire stem and thus in each wheel?

There are two TPMS systems our there. One puts sensors in the wheels and are powered by lithium batteries that last about 1o years. My Acura has this and my instrument panel can display the PSI or each tire. This is a much more accurate system but costly as each sensor is $150 (x4).

The other system uses no sensor sbut relies on the car's ABS system to detect that one wheel (the one with the flat) is spinning at the different rate than the rest and throws up a light on the dash. This system can NOT tell you which tire(s) is low, just there is a problem with at least one of the 4 tires, or more.

If this doesn't happen when the Nuvi is not in the car then it does point to the Nuvi as the culprit. Can you borrow another model or another unit and try it out?

[totalboard]

The CR-V has sensors in each tire but the instrument panel only displays a low tire and not which one. The Honda service department gave me a copy of US techline summary ATS 090907 which talks about Intermittent TPMS Codes 32, 34, 36 and 38. The report applies to 2008-10 Accord, 2007-2010 CR-V, 2008-2010 Fit and 2008-2009 S2000. It says the TPMS sensor sends a RF signal to the TPMS control unit and if the control unit fails to receive the sensor data, DTC 32, 34, 36 and 38 will be stored. The transmission failure can be caused by a faulty sensor, a faulty TPMS control unit, incorrect PDI (sensor not learned) or RF interference. It goes on to say some known sources of electrical interference are: Cellular phones connected to a 12 volt charger, DVD displays, etc. Others have commented on iPhone 3G as causing the same problem.
I have had both the control unit and sensors replaced. I do have an older Street Pilot I can try and will try switching another Nuvi to see if the problem goes away.
Thanks.

[kingmeow]

Hmmm, that is interesting. I would imagine that the TPMS system is very similar across the entire Honda product line, including their Acura luxury division. Yeah, my car is $40k but I see a lot of technology that should be common.

Try another unit and let me know if it happens. I hang out in the Acura forums and I have not come across any posts by anyone complaining about TPMS failure caused by possible handheld electronic devices.

Now I am curious. I'm about to break open a 255WT to replace my 260 so we'll have another data point by mid-week.

[kirsch92]

I have an 09 Honda Fit with TPMS. System has one sensor in each wheel.
I have no interference problems from a Nuvi 255W.
I have not seen any mention of this problem pop up in the Fit Freak forums either.

[Blue Flame]

You could call the FCC and see what they think...
http://esupport.fcc.gov/complaints.htm
Phone numbers are at the bottom...

[hmason]

I drive a 2009 Murano. I had a Nuvi 370 and never had a problem with the tire pressure monitoring system. I recently purchased a Nuvi 765T with traffic alerts. My tire pressure warning system goes haywire after about 10 miles of driving. It remains screwed up for several days even after removing the Nuvi from the vehicle. Once it reverts to normal, I reinstall the Nuvi and have the same problem again.

I called Garmin and they denied ever hearing of this problem! They said to move it to a new location. I tried that with no success. They need to get on top of this situation as it is a safety issue.

I have returned the unit and ordered a new model (1390T) with traffic alerts. When I receive it I will let all know if it also interferes with the tp monitor.

[totalboard]

I have turned off the Traffic Alert on my Nuvi 765 and decreased the display brightness (daytime at 90% and evening at 50%) and the TPMS light still comes on after around 15 miles.
I wrote Garmin and they were of no help. I spoke with Honda and they agreed there have been issues with RF Interference and are looking into it but do not have a solution yet. They wanted me to try it with the unit running only on the internal battery but when I operate it like that, the TPMS light still comes on.
I'm anxious to know how the 1390T will operate with your TPMS.

[BarryLL]

I have a '08 Honda CR-V and a TomTom Go 630 and I think I may be experiencing the same problem.

Just to be clear though, for us I think it's about 30 minutes of driving, and then it's the TPMS light (saying there is a problem with the system) not the TPMS tire pressue ("horse shoe") light that lights up. Also after about another 15 minutes it goes out and so far, doesn't come back on again during that trip. I'd also had BlueTooth turned on the unit and I think every time we've always had a full load in the car, kids with iTouches and cell phones etc.

I only noticed it after having Honda replace a couple of tires so I thought it might've been related to that. However as I thought about it I realized that we rarely use the GPS except on longer trips. (So I never thought to try just turning off the GPS when it came on and haven't had the opportunity since.)

I asked the dealer, they didn't know anything about interference problems, but happily chaged me $65 to pull the codes just to say that the system reported not being able to communicate with some of the sensors.

Do you have a contact at Honda that's been looking into this? I expect there to be finger pointing amongst the sensor makers, auto makers and GPS makers

[Boyd]

Well GPS'es have been in cars for awhile now, so I think the auto companies need to develop communications protocols that are robust enough to work without being interfered with.

The auto industry is having some growing pains with all the software and electronics in today's cars...

http://online.wsj.com/article/SB10001424052748704359504575045131917738188.html

[K9CHP]

I have not had that problem but being an amateur radio operator, I am somewhat familiar with RF interference. My first step would be to put some ferrite chokes on the power cable of the Nuvi. This is something you can try for a few bucks and they are available at Radio Shack. I don't know if they are the cheapest there, but at least available almost anywhere.

Amir K9CHP

[totalboard]

Do you have a contact at Honda that's been looking into this? I expect there to be finger pointing amongst the sensor makers, auto makers and GPS makers [/quote]

I spoke with Simon at Honda Automobile Customer Service at 1-800-999-1009 Ext. 117742. Their Business hours are Monday through Friday, 6:00 a.m. to 5:00 p.m., Pacific Time.

[dhlizard]

I have 2 different Chrysler vehicles, both with TPMS and neither of my Nuvi's with traffic antennas bother the systems.

Nuvi 765T
Nuvi 255WT