electrical issues

[N7RMK]

this will be a long post thanks for reading it to the end……...ok so here it goes. Last night I'm driving home from a great photo shoot at lake mead all is fine with the TB then with out any warning the radio shuts off all of the gauges in the dash except the tach and spedo stop reading anything, the ac blower continues to blow but its blowing hot air, all of the warning lights illuminate, cruise control stays on. head lights turn singles continue working uhf radio continues working and the truck continues to run fine.

then everything comes back on and seems fine. well for about 2 minutes it was fine!!!

then back to the exact same thing everything goes "dead" but truck keeps running.

as I'm driving down the road i try the windows they still work at this point but nothing else seems to work. as i pull into town i try to stop and get a bite to eat (priorities right) . not wanting to shut the truck off i go to drive thru. now the windows won't roll down so abandon the drive thru. (i think the windows originally still worked due to it thinking i had just turned it off and latched power was still there)

i get the truck home and shut it down. then i restart the truck. it fires right up but still back to the same condition. but now i realize that i don't have door locks along with every thing else that isn't working.

i notice that the security light is on as well so i use the key to manually lock and unlock the door hoping this may reset the security system as it has in other vehicles i have owned.

after i did the key in the door it won't even crank!!! at this point its 9:30 pm and been a long hot day i figure ill just look at it in the morning.

i attempt to use the key fob to lock the truck and get no response i manually lock the truck and go inside

so this morning i go out to start the search or the culprit and the battery is flat dead. only 4 volts!!!!

so i hook up the charger and start looking around with a multi meter.

i first check the rear fuse block for power as i read here that most of the parts not working are supplied power from there. i have power at the rear fuse block.

a few other things that i noticed before retreating to the air conditioning and hit the oftb forums while the battery charges.

1 thing i did notice was that the over head lights don't come on when i open the front doors but it does come on when i open the rear doors. i don't know if that means anything or not but i thought it to be strange.


so here i sit in a bad way i have read about the ignition switch being a bit wonky at best but after reading many posts i think my problems are running much deeper and with the blower motor still running its leading me away from that being the issue. i could be wrong. also with the battery being dead this morning i would think its not an open issue but something that is gone wrong and is now killing the battery.

thank you for reading this very long post i always have gone with there is never too much information when trying to figure something out. any help would be very appreciated.

[N7RMK]

problem solved. you guys are never going to believe what it was……..ok maybe you will!!!

it was the elm Wifi interface!!! if i ever figure out how to upload a photo you will see what one looks like when it nearly burt your truck to the ground and or took out your PCM

[Trail X]

All that was caused by an OBDII wifi transmitter that went bad? Yowsa.

I'm not sure I understand the mechanism in which it could take all of those systems down.

[Wahugg]

Could the adapter shorting out internally cause chatter on the network preventing other devices to 'talk', thus further preventing them from turning on? Roadie would know more about this for sure.

Or maybe the burnt up adapter is a symptom not the cause.

-Wahugg

[The Roadie]

Or instead of crap chatter it could have shorted the datacomm bus to 12v or ground. Still suppresses proper comm which explains all symptoms.

[N7RMK]

It was the elm adapter that was the cause. it was by complete chance that i discovered it being the issue. I'm going to assume that the truck felt it was being stolen with all that was going on. i had the key on while i was looking at the fuse guide and after about 10 minutes the security light went out and the stereo came on momentarily. after that the truck would start again.

this lead me to think ok maybe it is the ignition switch.

so first thing that needed to be removed was the elm obd2 adapter. as soon as i touched the adapter the stereo started making an intermittent sound as i removed it it went to a clean clear sound. i looked at the gauges and all was in working order.

I have been driving it all day with out an issue.

once i had time this evening i opened the elm adapter and notice a serious design flaw. not sure if it was the cause or not but its a two bored component. the smaller board is avow the main board and literally rests on the bare top of a capacitor. this could easily cause a short on the board and odiously cause some pretty serious conditions to the cpm.

at the end of the day I'm glad it was a simple fix and didn't cause any damage to my TB.
here is a link to the photo
https://www.facebook.com/photo.php?fbid ... =1&theater

[djthumper]

Wow, I am glad it turned out to be something simple.