justinlooney
New Member
So i have a 19 ram limited that i bought used 6 months ago with 78000 miles. Was fine for a few months then started getting a service electronic stability control message on the dash. So I went through checking connections and wiring didn't really find anything that i thought would cause an issue. I found out recently that there is a recall for that light coming on but they don't have a fix for it yet for my truck. If the esc message is on then my vacuum pump is constantly kicking on and off. I replaced the vacuum pump because it sound pretty rough but it still comes on and off just doesn't sound as bad. Also replaced the vacuum pressure sensor and pigtailed a new connector on. No issues with braking. I did all this before i found out about the recall. I say that because I don't know if it is related but I have recently over the last month or so been having issues with my battery dying and randomly having my truck throw every code on the dash and then saying no bus. windshield wipers go crazy ipc is resetting and this last time my truck got stuck in second gear then after i limped it home in second shifted to reverse to back in the driveway because i was hauling a trailer it died and wouldn't start. Also have had passive entry not recognize my key and then i try to unlock it with the fob and it doesn't work. So i use the key to unlock the door and the alarm would go off and the key was truck was unresponsive like the key wasn't present. So i pulled the horn fuse because it was early in the morning and ran inside to grab my other key just to verify that it wasn't my key fob battery. Have since changed batteries in both fobs. I have an oscilloscope so i started trying to track down what was keeping the truck on and the only thing that would let the can bus go quiet is if i unhooked the rf hub. so I replaced the rf hub because i thought it was keeping the truck awake and i was having issues with it recognizing my keys. My truck was great for a week and then it died. I recharged the battery and the then the very next trip i took i had the no bus issue again and have had a couple of times where is didn't recognize my key to start the truck. I haven't been able to drive my truck much and replicate it this week so i can try to unhook connections on the can bus while its having the issue. So far what i have been able to drive it has been fine other than it will die if i leave it sitting until lunch while I'm at work. I am at a loss on were to go next.
Attached are the codes after it did the no bus issue and the battery died on me. also attached the codes that came right back after i cleared them.
Any help is greatly appreciated.
The first three codes have been going on since the electronic stability control issue started and the low voltage differential signal code is new.
U120C Lost brake booster signal
ActiveABS(Anti Lock Brakes) ( 2 DTCs )DTC Description Status
C1082-02 Vacuum pressure sensor general signal failure Active
C1252-92 Vacuum pump control circuit performance-performanceor incorrect operation
ActiveRADIO(Radio) ( 1 DTC )DTC Description Status
B156D-00 Low voltage differential signal (LVDS) video cable Active
Attached are the codes after it did the no bus issue and the battery died on me. also attached the codes that came right back after i cleared them.
Any help is greatly appreciated.
The first three codes have been going on since the electronic stability control issue started and the low voltage differential signal code is new.
U120C Lost brake booster signal
ActiveABS(Anti Lock Brakes) ( 2 DTCs )DTC Description Status
C1082-02 Vacuum pressure sensor general signal failure Active
C1252-92 Vacuum pump control circuit performance-performanceor incorrect operation
ActiveRADIO(Radio) ( 1 DTC )DTC Description Status
B156D-00 Low voltage differential signal (LVDS) video cable Active
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