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Discussion Starter #1
Key points -
wipers do a single swipe, or short series of swipes
dash lights all light up, dash makes the bing sound
speedometer gauge bounces up and down

rpm gauge doesn't move
no loss in power
no odd shifting
nothing to indicate anything else abnormal

I'm hoping this may help others, since although it makes some sense, it also doesn't from what I've been told and seen before. Generally it's accepted that items like the SPOD won't cause issues, because they are connected directly to the battery and grounded, and therefore don't go use the Jeep's CANbus or TPMS. Using these items, or others using a direct-to-battery harness is considered a safe bet, and even I was taken aback a little by my recent find.

I was driving home from work with another Jeeper, and we turned our CB's on to talk. I had no previous issues with the CB or the Jeep, and my CB is hard wired - hot to battery, ground to an o-ring terminal on the grounding post in the front passenger footwell where the other Jeep harnesses are grounded.

First he said he couldn't hear me well, I was clear, but not loud. I thought the CB setting was off, maybe I bumped a dial. I keyed up a few times to see if he could hear me any better, and my headunit rebooted almost every time. I keyed up again for about 5 seconds and then it happened, a single swipe of the wipers, and my dash lit up and went crazy, the speedometer bounced, ABS, ESP, brake, brights, all of them flashed on and then off again. No loss in power, nothing indicating it was the Jeep having the issue.

I called back to him to pull over, just in case, and we pulled into a parking lot nearby. He came over and I told him what happened. My Jeep was still running, so we tested some things out. I could hear him ok, but not as loud as it could be, especially with us sitting side by side. I tuned every dial again, and keyed up, and we both watched the headunit reboot again.

I told him how everything lit up on the long key, so I keyed up again for 5 seconds or so - it did it again perfectly. The wipers swiped, the dash lit up, the speedometer bounced - but the Jeep ran smooth throughout.

We poked around and he pointed out my mic wire was crushed a bit. It had been that way awhile, I never thought much of it. I had someone slide the front seat forward and into the mic months ago, but I hadn't been using the CB much.

So we swapped mics. He didn't key up using my mic, just in case (can't blame him much), but I keyed up and he could hear me loud again. I keyed up for 10 seconds and no issues anymore at all. I tested again later with my old mic, yep, it's the mic somehow - and it's causing the Jeep to act up.

Now, I wouldn't have believed it if I hadn't seen it myself, I would think that's crazy - it's an "independent system", but somehow it's doing it. I haven't tested one other area I've thought of doing, but I'm not sure I'll get to it either. I was thinking of grounding it separately from the Jeep harness grounding post. Technically, it would still be grounded to the Jeep so I'm not sure it would make a difference - one reason I didn't test it.

At any rate, I put in another mic I had at the house, no more issues again. All I can think of is that there has been an issue in the ground fault somewhere that tripped the Jeep.

There are so many posts I have read here that have similar issues, and quite a few talk about having things wired separately with an SPOD or wired directly to the battery. I hope this can help someone else fix their dash flashing, warning lights, wipers swiping issue.
 

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Discussion Starter #3
This doesn't just apply to a CB, it's just how I found my issue. The point I am trying to make is that there an be things you don't think are related to the issue you are having, but they are causing it somehow.

I would never think my CB mic having a busted wire in the cord would cause my wipers to swipe, and my dash to light up, and gauges to bounce - but it did. If I hadn't been able to connect the action of the mic, to the electrical issues the Jeep was having, I would have taken it to the dealer, and the dealer would have found nothing wrong. I would then be pissed off even more because they would tell me I'm nuts basically.

I would be about then I would tell them what happened and they would tell me the CB is doing it (if I'm lucky), and then tell me I'm going to screw up the Jeep too. Then I would have been more pissed.

Now, if you have no electrical mods, this won't apply. All I'm saying is that it's worth the 5-10 minutes it takes to check it out, maybe disconnect the electrical item as well, and see if that fixes it.
 

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Discussion Starter #4
@ scottmphoto - I watched your video again. The order of events is interesting, you switched lanes, then the brake and esp came on, followed by the drop in rpm's and abs, ending with the sway bar light as the rpm's recovered. The only light remaining is the esp.

Have you had the wheel sensors checked and is the track bar adjusted to center and the steering wheel straight when you are driving straight?

Also, have you checked the battery cables and battery itself? There was a bad batch of batteries too, I ended up with one of those a few months back - it leaked and was bulging.
 

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I just posted this exact same issue in the communications forum before I found this post.

Mine is doing the same thing. CB has worked fine for almost a year. Now whenever I transmit, for a few seconds all the instrument lights come on, my headlights come on, and my wipers make a few swipes.

I don't see any problems with my mic cable but I suppose I could borrow one from someone and see if the problem persists.
 

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Following up on this....my issues HAD gone away for quite some time. I recently moved my antenna to another mount (due to selling my previous mount) and I'm having the same issue again. Tried using a buddy's mic but the issue still occurred.

Is driving me CRAZY!!!!!

Tomorrow I'm going to try a few more things:
1) My CB has 3 wires (1 for ground, one for 12V constant and the 3rd is set to a 12V on w/ ignition). I'm going to move that 3rd wire to the 12V constant.
2) My grounded through my gate so am going to run a new ground from the mount to the chassis.
3) My friends spare mic was pretty old so will pick up a new mic.

For me it's going to be harder to know when I have it resolved asit's intermittent.....I can talk on the CB for 30 minutes straight with no issues then suddenly this problem happens. Then it randomly goes away. I'm about to loose my mind over this.
 

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^^^It sounds like you have RF bleeding into you computer system. How high are your SWRs? Is your CB antenna base grounded good?
SWR was 2.0 as I recall.

Grounded good as far as I know but have read the gate isn't good for a ground. Will run a ground to chassis tomorrow. Just did item #1 above.

EDIT: I can confirm solid ground at all points that should have a ground. This includes the outer part of the coax at the radio end.
 

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Did some more testing.

Drove around the block and found issue still exists. But is very intermittent. No rhyme or reason to it.

One thing I did find.....when it does occur, it doesn't happen as soon as I key the mic. It happens when I actually speak into the mic.

Am going to ground the gate tomorrow and see if I can pick up a new mic.

After that I have no idea what to try.
 

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When you talk into your MIC, your are getting RMS, plus PEAK modulating power. So what you are saying makes sense!

So start by grounding your antenna to the frame, then try to get your SWR (standing wave ratio) below 1.5, flat is the best. Because what is happening, is you are getting RF, that is radiating off of you coax cable, because of the 2.0 SWR.

Another way of looking at it is, if you have a garden hose with some pin holes in it. With the hose opened on one end and you turn on the water, then very little will leak out of the pin holes, because the water is flowing without much resistance. Now, try pinching off the end of the hose,and watch the water squirt out the holes. This is the same thing that happens on a length of Coax, only it's RF that is leaking off of the line, because the SWR, is pinching off the coax line!

I have been a Ham extra class radio operator, for about 45 years, so trust me on this one!!!!!!!!
 

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Makes sense to me! :)

Questions: Why would it be so intermittent and why did it work for a year with no issues? Just curious.

Thanks
 

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Removing the PAC didn't work.

About to order new coax as well.
 

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^^^Yes, new coax is a good idea, and (now don't laugh), wrap the coax in tin foil if needed, because tin foil shields RF..........:thumb:
 

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^^^Yes, new coax is a good idea, and (now don't laugh), wrap the coax in tin foil if needed, because tin foil shields RF..........:thumb:
Hey, I'll try anything at this point. LOL

Will run the new coax without tucking it away and see what happens. Also adding a right angle connector at the radio end as the mount location was putting a good bend in the coax. Want to also rule out a short because of it.

Also ordered a new mic. Figured may as well replace everything but the radio.

Parts will arrive in a few days. Will keep ya posted.
 

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Let me give you a perspective that may help you pursue a remedy for the obvious case of common mode radiation that is giving the JK TIPM fits.

All antennas that present a characteristic impedance, that does not match the impedance of the transmission line, will return the reflected power (that was not radiated because of the impedance mismatch) to the outer conductor of the coax cable. This can amount to an appreciable level of RF that radiates into the cab of the vehicle.

You can be certain that it is common mode radiation that is causing your problem.

Common mode currents will always be present, since a perfect match is impossible to achieve in a real world application.

What has caused so much confusion, in this case, is the apparently random appearance and disappearance of the symptoms.

First thing to know is that the vulnerability level of the TIPM is fixed as it is a passive (in this case) device.

The second thing to know is that the reflected power from the antenna is widely variable because the antenna impedance is widely variable because of "Near Field Loading". Anything conductive within one wavelength of the vehicle will change the antenna loading and thus the VSWR. This includes the changing location of the vehicle with regards to trees, buildings as well as soil conductivity.

The third thing, to know is that the threshold of disruption of the TIPM is very narrow. A very small amount of common mode radiation increase will bring about disruption if the common mode field is very near the TIPM threshold of vulnerability.

Normal degradation of components and changes of vehicle configuration and vehicle surroundings will cause measurable changes in VSWR. You have already noted a less than ideal level of VSWR and all your efforts should be put into bringing it as low as possible.

You will never eliminate reflected power and common mode currents but you can bring them below the TIPM malfunction threshold.

If normal antenna refinements fail to bring down the VSWR, it is possible to install a choke at the base of the antenna (external to the cab) to reduce the common mode current inside the vehicle. This is a technique widely used by hams and is well documented on the net.


Good luck
Phil
 

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An additional thought, after re reading your initial post. You mentioned ground changes. Normally this would not be a thing I would recommend, but in this case, being so obviously close to the TIPM threshold, it might be worth a try, but only after you have brought down your VSWR. By changing a key ground location, it is possible, in theory, to change the path of the common mode current that has entered the TIPM connectivity, and affect the disruption. Won't be able to quantify (measure) it however.


Your observation regarding the microphone falls within the uncertainty of the TIPM threshold and while interesting, is not conclusive. I have worked systems where microphone position, cord compressed, stretched, etc had effect that was not related to microphone defects. Not all devices can be relied upon to behave identically, in all cases in a strong RF field.

Phil
 

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Ran a ground from the antenna to the chassis just in case I wasn't getting a good ground via the gate. Haven't had a chance to test it out yet.

New mic and coax arrive Friday.
 

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Ran a ground from the antenna to the chassis just in case I wasn't getting a good ground via the gate. Haven't had a chance to test it out yet. New mic and coax arrive Friday.
Welp, that didn't do any good.

Will try again Friday when new parts arrive.

This is nuts.
 

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Cheer up :bop:

I did a quicky, temporary, install on my '14 JKUR for my trip to Alaska and did every thing "wrong" (even though I'm a retired tech) and had no problems. All temporary except for the antenna mount which I would "roast" any one else for doing and it worked well enough. VSWR was about 2. and had no squawks from the Jeep. You can nail it!

Phil
 
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