INSTALLING AMATEUR AND CB RADIOS IN 2016 TACOMA

@Boondoggler my method of troubleshooting is to replace individual possible points of failure to see if there is an impact. One of the first things that came to mind is that this "smells like" an electrical interference issue. Possibilities for that might be:
1. How the radio power interacts with vehicle power. You mentioned that you tried a completely separate battery I believe, but under the hood. Try an in-cab 12v battery with wire routing not going anywhere near the dash or beyond the firewall. Keep the length of those wires on the conservative size.
2. RF energy off of the coax may be too close to something important on the truck. Examine the route that the coax takes and where it may come close to a computer system. Come to think of it, I think there was another person somewhere in TacomaWorld that had this exact root cause. I would even go as far as disconnecting your existing coax and run a new temporary coax that does not route anywhere near the dash or beyond the firewall to something like a mag mount on the cab roof. This is a temporary setup for testing only. If you do not have that antenna solution or spare short coax run, the local club is likely to be able to help.
3. Check your SWR. High SWR lends to more RF bleeding off of the coax, especially with the higher power output as you described.

 

@SigBoy hey man thanks for checking in. I actually did the things that you mentioned and would still get the intermittent problem. Here is the skinny on how things played out.

I took the truck to the dealer, we were not able to repro the issue in the bay. I drove the vehicle out of the bay, parked it next to a connex container on the lot, while my foot was on the break pedal, I keyed the mic to transmit and got all of the same error codes. I drove the truck back into the bay and showed the tech. The tech said that error codes say that the truck thinks I am stepping on the throttle at the same time that I am stepping on the break pedal. Then the tech pointed out that the cable for the hand held was touching the cable for the throttle position sensor. The kept the truck over the weekend and also recommended that the pedal commander that sits inline between the gas pedal and the throttle position sensor, that RFI could be getting into the system via the pedal commander.

So, I went back to the shop that did my overland build and also sold me the pedal commander. We got on the horn with the manufacturer of the pedal commander. He said that he'd received three other reports of RFI getting picked up by the pedal commander. So, he sent us a new one, no charge, and we replaced it an relocated the handheld wire so that it was not in contact with any wires under the dash.

Since then my signal reports come back 5x5. I am really happy with the build, the radio, and everything else.

 

One thing I learned over the past couple years dealing with two-way radio operating on the General Mobile Radio Service (GMRS) and their antenna systems is that the best way to block Radio Frequency Interference (RFI) is to encapsulate feeder cables in a ferrite choke, detailed exhaustively here.

 

Ya man, thanks for the tip. I installed quite a few of them. I got a big box from HRO. The work well.

 

I have both a HAM install and CB install. The CB antenna is mounted to a @CaliRaisedLed Ditch Light Extension bracket. I am removing the CB and going to GMRS with an NMO mount antenna. I'd like to find a ditch light extension bracket for NMO mount, but have had little luck in finding one. Does anyone know of such a beast? Thanks!

 

The benefit in clarity and range through obstructions with a roof-mounted NMO mount and proper antenna for GMRS cannot be understated. None of the ditch light mounts or extensions reach far enough away to prevent capacitive coupling.

 

Yeah, I know. My HAM dual band antenna is roof mounted. I really don't want a 2nd roof mount antenna.

 

Gotcha, understandable.

 

I am currently, finishing up an install on my 2018 TRD DBCB. Before I started I went to most of the Ham Forums and searched for install threads, things to pay particular attention to. The most common reason people had discrepancies with the electrical install part was the " ground Loop" scenario.
And that particular condition can have an effect on multiple on board systems. Most radio manufactures all say to connect the positive to positive terminal, and the negative to negative terminal. This is wrong according what I have read. For instance what if someone does maint on your truck they remove the Ground from the battery and when they went to connect it back they didn't connect the chassis ground, now when you start your vehicle its looking for a ground and the vehicle uses the radio ground, hundreds of amps using the radio for ground. Might be something to look at.
The link below has some good info also, QRZ.com has a thread called
"Mobile Radio Install DC Power Myths"
http://www.k0bg.com/
The Radio I'm installing is over 23 years old been sitting in a Texas attic for 20 years, to my surprise lit right up no smoke.

 

Thanks for the info!

 

Thanks for a great writeup. I've got a Yaesu FTM400-xdr that I'm really enjoying for the most part. For the most part only because when I turn on my LED fog lights, my roof rack lights or my DRL, the reception diminishes because of an RFI problem that I haven't been able to solve. If I use the LED light bar on the bumper, regular headlights or high beams, I don't get any interference. The antenna is mounted to the passenger side hood and I've got a braided strap going from the mount to the same bolt you show, and also enters the passenger compartment through the drain tube grommet like you show. I've already gone the ferrite route and placed beads on the wiring from the fog lights, the upper light bar and the DRL harnesses but that really didn't seem to affect anything. Chassis is properly grounded to the seat bolt, just like yours. I currently have the radio wired through a Switchpro 9100, but have tried wiring +/- direct to battery and that had no effect at all. Both, the roof top light rack and the bumper mounted light rack are wired through the Switchpro as well, and the fog lights use the factory stem on the column to activate so I would think that the Switchpro is not the cause of the interference. Any suggestions would be greatly appreciated. I have not tried using a handheld in the cabin to see if it would be affected by interference.

 

Definitely try this. If you hear nothing, connect the portable to your antenna. Report your findings.

If it's only in the power leads, it's easier to solve.

 

I just made an accidental discovery, and this seems like the best place to mention it.
I have a 2018 TRD Off Road.
Mounted to the back of the steel cabin are a Yaesu FTM-400XDR for VHF/UHF, and a Yaesu FT-891. Antennas exit the cabin via bulkhead connectors thought the steel. Aux battery is in the bed, with well decoupled power coming through the steel wall as well.
My VHF/UHF antenna is half-wave, mounted on a custom post behind the cab. Everything about this works great.

My HF antenna is mounted near the back of the drivers side bed rail. I alternate between a 104" steel whip, and 10m, 20m, or 40m hamsticks. These are connected to a Yaesu FC-40 tuner located in the little storage box on the drivers side. Everything is well grounded. It generally works well from 40m to 6m. On 40m, I can communicate about as well while driving as I can while parked.
But, on 20m especiallly, when I start the truck, the noise floor goes up to S7/8, and I only hear an occasional very strong station. When I turn the truck off, the noise floor drops, and I can hear many stations. On good days, I have made contacts as far away as Japan from the mall parking lot.

Then, I got my new BAMF steel rear bumper.

While the old bumper was off, I needed to drive to Lowe's. I was surprised to find that my noise floor was down to S4/5. Apparently, the culprit was either the ultrasonic parking sensors, or the blind spot monitoring radar.
After putting the new bumper on, I re-installed the backup sensors. When I turned on the parking sensor switch, I got a warning on the dash that there was a problem in my backup detection system. So, I connected the BSM radar units, and strapped them out of the way inside the corners of the bumper. (These won't work with the steel bumper). After that, the backup warning sensors work, but the noise floor is down to about S4/5 on the 20m band. Apparently, the steel bumper blocks most of the RFI that these sensors produce.

I need to do more investigation, but I seem to be on to something.

 

Install RF Chokes everywhere. Re-read the article to see where I installed them. Keep your wires away from the main wire cabling bundle in from the engine bay. See how I ran mine to avoid that bundle.

 

Old school is very cool...

Made a bracket. Bolts to the passenger side of the console. Doesn't interfere with passenger's leg at all.

Wilson 1000 magnetic on center of roof. Best reflective surface on truck for RF.