Call Search
     

New to Ham Radio?
My Profile

Community
Articles
Forums
News
Reviews
Friends Remembered
Strays
Survey Question

Operating
Contesting
DX Cluster Spots
Propagation

Resources
Calendar
Classifieds
Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement
About eHam.net

donate to eham
   Home   Help Search  
Pages: [1]   Go Down
  Print  
Author Topic: RFI problem with my Pickup  (Read 4378 times)
KD0MEO
Member

Posts: 3




Ignore
« on: June 15, 2018, 12:30:05 PM »

I recently purchased a 2007 Chevrolet Silverado it has a 5.3 engine.
Now this is my problem.
I have a Yaesu FTM 100dr mounted and all wires run from the Battery thru the Passenger side.
When I key the radio my Oil Pressure Gauge drops to 0. When I un-key it goes back to 60.
If I say over 3-4 words it drops to 0 and the Warning Low Oil Lamp come on.

I even moved the antenna to the back rail of the pickup bed, no changes.
Next i took my Yaesu Ftm1 dr and set in the pickup and keyed and it would drop but much slower.
I Would not drop when I went to UHF.

So any Ideas how to stop this from happening would be appreciated.
I need to be able to talk as I am the Local ARES Emergency Contact.
And a local weather spotter.
Thanks
Dale  KD0MEO
Logged
KE5PPH
Member

Posts: 64




Ignore
« Reply #1 on: June 17, 2018, 09:56:39 AM »

Do your power leads run next to the ECM? I don't have a Chevy, but in Fords that grommet is right under the engine computer..  Check out http://www.k0bg.com/     
Logged
KD0MEO
Member

Posts: 3




Ignore
« Reply #2 on: June 22, 2018, 10:22:57 PM »

Thanks. KE5PPH for the reply
I have run the wires thru the passenger side down the door and in the cab thru the wiring access for the power windows so im  away from the ECM
Something I have noticed is if I key up on UHF it doesnt bother the Oil Pressure Gauge.

So it must be just VHF.

Now if I can figure a way to block it from the rf on just the Oil pressure gauge so VHF doesnt bother it.
Thanks for the Link to the web site. It is interesting.
Logged
K5LXP
Member

Posts: 6167


WWW

Ignore
« Reply #3 on: June 23, 2018, 06:23:29 AM »


Being a 2007 the gauges are all driven from one or more processors, not like 1950 where there was a sender/sensor, a wire and a gauge.   Not sure you'll be able to selectively cure RFI like this.

What I'd be checking is how well the ground side of the antenna is bonded to the sheet metal.  Also if there's a bad shield connection at the radio end.  Thinking there might be common mode on the coax shield that could be coupling into the vehicle wiring.  Another thing to try is bypassing the DC lead, and maybe ground the negative lead and the chassis at a few different points.

It could be that whatever system that's affected is especially susceptible to VHF but in my experience it takes a pretty good dose of RF to do that.  That implies there's a lot of RF on the inside of the vehicle and not going out the antenna as it should.  So checking for coax common mode and DC cable resonances would be my plan of attack.

Mark K5LXP
Albuquerque, NM
 
Logged
KD0MEO
Member

Posts: 3




Ignore
« Reply #4 on: June 30, 2018, 10:31:32 PM »

Thank You.
I will again double check my grounds.

The sensor for the oil pressure gauge is next to the fire wall on the top ob the motor.
Ive had some friends at our local club tell me to wrap the sensor with aluminum foil to reflect the rfi from getting to the sensor.
Does anyone think this will help?
Logged
K5LXP
Member

Posts: 6167


WWW

Ignore
« Reply #5 on: July 01, 2018, 05:07:27 AM »


If it's radiated energy causing it, maybe.  But it could also make it worse by reradiating the energy that's there.  If it's conducted then probably not.  You're also assuming it's the sensor that's affected but being a "digital" system it could be interfering with a processor or other circuitry in an entirely different location.  Wouldn't hurt to try but I wouldn't expect a miracle.

Mark K5LXP
Albuquerque, NM
 
Logged
KE8BHP
Member

Posts: 1




Ignore
« Reply #6 on: July 31, 2018, 08:09:20 AM »

Did you ever get this resolved? I have a 2005 gmc Sierra with the same problem so I'm interested in what you may have found out
Logged
WB4SPT
Member

Posts: 784




Ignore
« Reply #7 on: July 31, 2018, 10:20:42 AM »

pre 2007 GM gas reportedly does not use CAN sensors.   Soooo, I would suggest a mix 61 ferrite close to the black box that the sensor feeds into.  Obviously, a lot easier to type this than to implement if you don't know where that box would be and which wire harness it arrives in. 
Logged
Pages: [1]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!