Issue with LPP false alerts

[LeVer2k2]

Hello, all. I have had my LPP about 3 weeks now and I'm having issues with false alerts, i.e. the 3-beep alert and, more frequently, full laser alerts. It definitely doesn't miss a beat when I encounter actual LIDAR (Photo-LIDAR cameras, LEO controlled guns) but it's annoying me with these falses.

I usually get the full laser alerts as I am completing a turn. That could be when coming around the bend of an on-ramp to merge with interstate traffic or simply turning out of my parking lot at home. The 3-beep doesn't happen as often, and I'm not really concerned about it, as it is merely an indicator of an unidentified laser source. Here in the Bethesda, MD area, I'm surrounded by Mercedes, BMW, and Infiniti cars. The 3-beep is to be expected every once in a while due to the presence of laser-assisted cruise control.

However, I have also started to notice a 3-beep immediately followed by a full alert. That sounded very familiar to me as I remembered reading about someone (I believe named corkguykev) on the kmph forums having the same problem.

Things that I have tried to fix the problem? I bought RF/EMI chokes the first week to reduce any interference I could be getting from other cabling. I made sure that the control box was grounded at a good grounding spot. I tried keeping the face off of my stereo so that no power ran to the stereo or to the amplifiers in the back of my vehicle. I was initially concerned that the power cables for my stereo equipment were causing excessive interference with the signal wires for the laser heads, but the false alerts continued even without power through those cables.

I have also used my Canon digital camera to look at the heads in parking mode. From what I observed, the heads operate normally, firing roughly once every second when detecting anything in front, and increasing frequency when the object is brought closer.

The last thing I tried just a few minutes ago was to cover the heads with dark paper on my way home from work. Even with the heads covered, and the parking function no longer sounding, the false laser alerts continued. I stopped to fuel my car, removed the paper, and have now started to notice that the indicator light is randomly remaining unlit and then starting to flash again. Or maybe some flashes appear not as brilliantly as the others. If some flashes are just too dim, I'd lean towards it being a voltage problem.

Aside from tidying up the wiring behind my pedals to keep the power cables and signal cables isolated from each other, the only thing I can think of doing is change the location of the positive (+) wire for the control box. It is currently clipped into the ignition power wire, so it turns on when the car is either in ACC mode or the Start and On positions. I will try tapping into my cigarette lighter wiring. If that does not work, I have no idea what to try next. I don't see any signs of water in the heads, and there hasn't been any substantial rain since I got the system.

Does anyone have any ideas of what else may be causing this? Hopefully, changing the power source will be the end of this problem.

[eire05]

check the LPP bracket isn't touching any metal or the screws goign into it

I kno theres a post of someone using metal shiedling for the transpnder cable
have a look for that.

ALso check the cable isn't near large noise areas like alternator etc

[LeVer2k2]

Originally Posted by eire05

check the LPP bracket isn't touching any metal or the screws goign into it

I kno theres a post of someone using metal shiedling for the transpnder cable
have a look for that.

ALso check the cable isn't near large noise areas like alternator etc

Thanks for the quick reply. I forgot to mention that I did cover the metal area of the car just above the screws with soft-sided Velcro since I noticed that they were touching.

I'll check the routing of my wires and make sure they aren't near noisy sources and also try shielding the wires. I guess I was hesitant about doing it before since routing them through the firewall was such a chore to begin with.

[corkguykev]

hi there.

yep i had this happen too. i had never had any 3 beep alerts before that but it just kept going off every time i got the car up to 3900 RPMs or so. full jamming false alerts too

i also found that the led would flash seldom and/or very weakly also and sometimes it would just not power up again after i switched it off to stop a false alert until i lowered the engine RPMs or even turned it off altogether

after some time wondering and calling KMPH UK about this we came to the conclusion that it was the cars CANBUS system that was causing it and i switched over to the cigarette lighter as a power supply as that was easy enough to tap into and fortunately it was a "cleaner" source.

what type of car is yours? mine is a ford focus.

what did you earth the unit to? i used a bolt going into the bodywork on mine and a spare power supply that was behind the switch blank (that i mounted the kill switch on) on the centre column to power mine.

basically how i got mine to work in the end was by using the positive and negative wires on my cigarette lighter wiring to power the LPP directly. even using the body of my car as an earth was a no-go for some reason. unfortunately i have to remember to switch on and off my LPPs now as the cig lighter is not turned off by the ignition but it does work perfectly on that as its a more stable power source than i was previously using.

doing this also should be the end of your problem but if not then it would be possible that the damage has already been done to the system as it was in mine. it bought me some time but i had to get it replaced as the problem reocccurred unfortunately but since i hooked up the new one to a correct power supply from day one it has been working flawlessly

i hope this helps as i went through the same and its a real pain in the a$$

[LeVer2k2]

My car is a 2001 Dodge Neon. My system is grounded to the steel frame inside the fuse access panel to the left of the steering column. As far as the issue with the unit not coming back on immediately after cycling the power goes, I have noticed that it may delay for just a couple of seconds, and on a couple of occasions, I had to turn it off again to get it to turn back on. I'm going to keep the power turned off tomorrow until I am actually able to change the wiring.

Thanks a lot for the feedback guys.

[LeVer2k2]

Looks like I fixed the problem. I rewired the control box (+) to the positive wire of the cigarette lighter and the (-) to the negative wire of the lighter. I also separated the bundle of laser head signal wires from the 8-guage power wires running my amplifiers. After taking it for a test drive, I no longer got any of the false alerts that usually appeared with each turn I made. I got no alerts of any kind, but that's ok since I did not catch sight of any laser sources. I'll know if it's working for sure on my ride home from work today.

In doing this, I relieved myself of the stress from thinking my new equipment was malfunctioning or possibly damaged, but also discovered something about my car that really pi$$ed me off. I originally grounded the control box to a steel block inside the fuse access panel. This block is what the actual fuse box is mounted to and it also has an easily accessible hole for grounding. It is even labeled "COM". My car alarm and stereo are also grounded here.

The problem? This block is totally brown from oxidation/rust. I tested the resistance between the block and a bolt on the actual frame of the car, and the resistance was .7 ohms. Almost an entire ohm. Given that the multimeter itself reads .1 ohm when the leads are connected together, and that the resistance between any two bolts on the frame also read .1 ohm, I concluded that this block lost some of its conductivity due to the rust. You would think that if they wanted that to be used as a ground, they would have constructed it out of higher grade steel that would not so easily rust and was better mated to the frame of the car.

Now I'm starting to wonder if this apparent grounding loop is what started all this mess for me in the first place. Before purchasing the LPP, I had an Escort ZR3 that started falsing for what seemed no reason at all. The heads for the ZR3 were originally damaged by a mechanic, and replaced at his expense. Later, false alerts from the ZR3 heads and the 8500 itself started appearing on the 8500 display when hitting high RPMs, even when the ZR3 function was turned off. Thinking that my ZR3 system was toasted, I got frustrated and removed the heads. The 8500, still connected to the junction box, continued laser falsing at high RPMs. I turned its laser function off, and, a few months later, got my first speeding ticket in more than 3 years. Fortunately, that drove me to place the LPP in my car 2 weeks later.

I'll try grounding the ZR3 junction box to the same spot as my LPP. If that works, I'll then have high and low protection against laser again.

[corkguykev]

Glad to hear that you have solved the problem

i hope it stays solved now, i doubt all the 3 beep falses yiou were getting were due to cars with laser assisted cruise control TBH. since i solved my own bout of this issue, i have had only one 3 beep alert and i was able to find the cause for this. an automatic barrier laser sensor in a hotel car park. other than that it stays quiet unless i get hit, which has been happening quite a lot as of late

with the ZR3s and LPPs working together (hopefully) you should be well protected

[LeVer2k2]

Thanks. It's funny that you mention how you hardly hear the 3-beep alerts anymore. I was getting so used to them, I was looking at the controls like "Sh!t, I hope I didn't just break the thing." . I hope this drive home is just as positive as my test drive was.

[corkguykev]

Originally Posted by LeVer2k2

Thanks. It's funny that you mention how you hardly hear the 3-beep alerts anymore. I was getting so used to them, I was looking at the controls like "Sh!t, I hope I didn't just break the thing." . I hope this drive home is just as positive as my test drive was.

no problem .

i went from having a perfectly working LPP (with no falses of any kind) to what happened to you so i knew something was up with it straight away. it took a few months to crop up in my case though

if these false alerts are something that you are used to, then you are in for a pleasant surprise. from my experience with it working correctly, you will forget its there and i do find myself checking if my leds are both flashing every so often just to make sure my LPPs (front and rear) are actually switched on .

granted there are no laser assisted cruise control fitted cars in my area nor have i ever encountered any so i cant predict whether or not you will get the odd 3 beep false now and again but im sure it will be a lot less often that you have been experiencing