# Stumped To This Point **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** sonoma, gmc\ **Created:** [November 18, 2021, 9:13pm UTC](https://community.cartalk.com/t/stumped-to-this-point/180719 "2021-11-18T21:13:46Z")\ **Posts on this page:** 20\ **Page:** 3
**Author:** ![bing](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bing/32/4619_2.png) [@bing](https://community.cartalk.com/u/bing)\ **Post date:** [December 1, 2021, 2:24am UTC](https://community.cartalk.com/t/stumped-to-this-point/180719/42 "2021-12-01T02:24:17Z")
Well we part company. I’m beyond the point of liking challenges or crossword puzzles. Plus he said he is in current need of the vehicle which makes it less fun. ---
**Author:** ![wentwest](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/wentwest/32/6073_2.png) [@wentwest](https://community.cartalk.com/u/wentwest)\ **Post date:** [December 1, 2021, 8:02am UTC](https://community.cartalk.com/t/stumped-to-this-point/180719/43 "2021-12-01T08:02:29Z")
That’s a sunny way to view a very cloudy situation. The frustration and depression of confronting something like this is terrible, and I feel like @ok4450 is a brother in a fight. I’d really like to help get this figured out, and I can’t. ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [December 2, 2021, 12:25am UTC](https://community.cartalk.com/t/stumped-to-this-point/180719/44 "2021-12-02T00:25:43Z")
Other ideas. 2 amps means something is dissipating 2 X 12.5 = ~~50~~ 25 watts of power. That’s quite a bit, and should be showing up as a temperature difference somewhere. Maybe one of those infra-red temperature gadgets might help diagnose where the power is going. 25 watts is on the order of a light bulb, so double check no light bulbs are on anywhere, including places like the glove compartment, trunk, engine compartment. Good idea to check each of the door switches, that they are working and not acting flakey, esp the driver’s side. ---
**Author:** ![weekend-warrior](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/weekend-warrior/32/26122_2.png) [@weekend-warrior](https://community.cartalk.com/u/weekend-warrior)\ **Post date:** [December 2, 2021, 12:48am UTC](https://community.cartalk.com/t/stumped-to-this-point/180719/45 "2021-12-02T00:48:29Z")
I remember reading somewhere about someone with your year truck having a similar problem. and I believe the radio was the problem causing the draw. just a thought ---
**Author:** ![fleetmanager](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/fleetmanager/32/24111_2.png) [@fleetmanager](https://community.cartalk.com/u/fleetmanager)\ **Post date:** [December 2, 2021, 1:51pm UTC](https://community.cartalk.com/t/stumped-to-this-point/180719/46 "2021-12-02T13:51:40Z")
Is that math correct? ---
**Author:** ![art1966](https://avatars.discourse-cdn.com/v4/letter/a/77aa72/32.png) [@art1966](https://community.cartalk.com/u/art1966)\ **Post date:** [December 2, 2021, 2:23pm UTC](https://community.cartalk.com/t/stumped-to-this-point/180719/47 "2021-12-02T14:23:28Z")
Yes the math is correct. However, 50W is like a low-power 110/120VAC household incandescent bulb. I’m not gonna research it right now, but my recollection is that automobile bulbs are more on the order of 5-watts (about 400 ma at 12VDC). Even so, a single bulb left on – typically in the glove box or the trunk, where it is not seen – can drain the battery overnight. But OK4450, and all the regulars here, know that. ---
**Author:** ![fleetmanager](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/fleetmanager/32/24111_2.png) [@fleetmanager](https://community.cartalk.com/u/fleetmanager)\ **Post date:** [December 2, 2021, 2:55pm UTC](https://community.cartalk.com/t/stumped-to-this-point/180719/48 "2021-12-02T14:55:45Z")
Really? 2X12.5=50 Are you sure? I keep coming up with 2X12.5=25. A 1157 bulb is 5/27Watt. A 6054 headlamp is 35/55Watt. OK4450 would definitely know if there was a lamp with the brightness of a high beam headlight on somewhere in his vehicle. ---
**Author:** ![art1966](https://avatars.discourse-cdn.com/v4/letter/a/77aa72/32.png) [@art1966](https://community.cartalk.com/u/art1966)\ **Post date:** [December 2, 2021, 3:00pm UTC](https://community.cartalk.com/t/stumped-to-this-point/180719/49 "2021-12-02T15:00:57Z")
Oops! That’s a “2”, not a “4”. (Or maybe I was seeing 2 x “25”, mis-glancing the “12.5”.) Still, 25W is like an appliance bulb – stove or refrigerator. (YEs, some of them are 40W.) Two-amp drain would be around five typical automotive bulbs. ---
**Author:** ![fleetmanager](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/fleetmanager/32/24111_2.png) [@fleetmanager](https://community.cartalk.com/u/fleetmanager)\ **Post date:** [December 2, 2021, 3:11pm UTC](https://community.cartalk.com/t/stumped-to-this-point/180719/50 "2021-12-02T15:11:37Z")
You do know that “typical” automotive bulbs vary in wattage from, less than 1 watt to over 100 watts. ---
**Author:** ![bing](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bing/32/4619_2.png) [@bing](https://community.cartalk.com/u/bing)\ **Post date:** [December 2, 2021, 5:28pm UTC](https://community.cartalk.com/t/stumped-to-this-point/180719/51 "2021-12-02T17:28:57Z")
> [@art1966](#): > > Even so, a single bulb left on – typically in the glove box or the trunk, where it is not seen – can drain the battery overnight. I’m not going to worry about the math. I believe the max allowed for headlights here is 55 watts. At any rate yes, a single bulb can cause a problem. Wife was parked at the airport for maybe 2-3 days. The one she was with didn’t close the trunk completely so the trunk light was on. Car was deader than dead when she came back. Airport service was not good enough to start it and had to call the motor club to boost it enough to get it started. The battery was not that old either but swapped it anyway. See my other comment on interior lights on and enough to drain the battery. ---
**Author:** ![fleetmanager](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/fleetmanager/32/24111_2.png) [@fleetmanager](https://community.cartalk.com/u/fleetmanager)\ **Post date:** [December 2, 2021, 6:50pm UTC](https://community.cartalk.com/t/stumped-to-this-point/180719/52 "2021-12-02T18:50:16Z")
I agree completely, I have diagnosed many Trunk/glove box/Dome light issues. My argument was solely on the math and the wattage claims. ---
**Author:** ![wentwest](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/wentwest/32/6073_2.png) [@wentwest](https://community.cartalk.com/u/wentwest)\ **Post date:** [December 2, 2021, 6:56pm UTC](https://community.cartalk.com/t/stumped-to-this-point/180719/53 "2021-12-02T18:56:48Z")
All very true, but here we have an experienced owner who has pulled all the fuses. I can’t think of a light bulb that is not fused in a vehicle. However, the radio may well have a direct connection to a power source, with a fuse inside the unit itself. The various computers will certainly be connected as well. ---
**Author:** ![fleetmanager](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/fleetmanager/32/24111_2.png) [@fleetmanager](https://community.cartalk.com/u/fleetmanager)\ **Post date:** [December 2, 2021, 7:09pm UTC](https://community.cartalk.com/t/stumped-to-this-point/180719/54 "2021-12-02T19:09:29Z")
Agreed, OK4450 would see a bulb illuminated if that were the problem. @ok4450 Just a thought, the DERM for the SRS has power all of the time not fused through the fuse box, did you try disconnecting the DERM? (Diagnostic Energy Reserve Module) ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [December 2, 2021, 11:18pm UTC](https://community.cartalk.com/t/stumped-to-this-point/180719/55 "2021-12-02T23:18:01Z")
> [@fleetmanager](#): > > math correct? oops! Sorry, I will correct. ---
**Author:** ![ok4450](https://avatars.discourse-cdn.com/v4/letter/o/e9bcb4/32.png) [@ok4450](https://community.cartalk.com/u/ok4450)\ **Post date:** [December 3, 2021, 3:38am UTC](https://community.cartalk.com/t/stumped-to-this-point/180719/56 "2021-12-03T03:38:44Z")
Had to get away from that thing (mostly) for a few days. Other fish to fry. The oddities continued. Security light and glitches still exist but… For the past 3 days I can lean in the window, hit the key, and fires right up/runs good. But now and then the battery will go dead in a few hours. Other times will stay up for days. Now the weirdness… The current draw at all times now is 71 Milliamperes which should be normal and acceptable. At times with a VOM connected I can watch the battery voltage drop by 1/100th of a volt on a regular basis. When it hits the 10s weak battery and solenoid chatter. Most of the time the battery stays on 12.7-8ish or so. The Milliampere check never exceeds 71 no matter what during all of this. So that brings up 2 points. One. My meter is off. I have 3 digital and one analog. They all give the same readings. Two. The battery (year old and tested good repeatedly) is weak. It takes a full charge quickly and holds up. I even pulled the battery out of my Lincoln (850 CCA,11 months old, no issues) and connected it to the truck in parallel. That gives it about 1400 CCA total. A few times it has run both batteries down in a matter of a few hours and that falls into the impossible category as the 71 mAs is never exceeded. I have to say that this is the first time in my life I’ve run into something like this. I went out tonight (truck not touched since yesterday) and hit the key. Started right up/runs fine. Symptoms have been all over the map. Also checked tonight and battery is holding 12.8 with 71 mAs current draw. My sister says it has to be poltergeists and I’m starting to wonder… I have not disconnected the DERM yet but checks have shown there is no power going through any leads other than the fuse box. I will give it a try tomorrow anyway. Current draw at the fuse box or even at the battery terminal is never more than 71 mAs. The 2+ amps draw seems to have packed its bags and left town…or it’s hiding out waiting for a return. Thanks for all advice. It is appreciated more than I can say. ---
**Author:** ![Marnet](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/marnet/32/41_2.png) [@Marnet](https://community.cartalk.com/u/Marnet)\ **Post date:** [December 3, 2021, 5:18am UTC](https://community.cartalk.com/t/stumped-to-this-point/180719/57 "2021-12-03T05:18:30Z")
@ok4450 I’m very sorry you are having such a baffling problem. Hang in there. And stay safe, sir. At the regulars offering help, this discussion thread epitomizes the best of what this forum can be and so often has been over the almost twenty years I’ve been reading here. ---
**Author:** ![bing](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bing/32/4619_2.png) [@bing](https://community.cartalk.com/u/bing)\ **Post date:** [December 3, 2021, 6:01am UTC](https://community.cartalk.com/t/stumped-to-this-point/180719/58 "2021-12-03T06:01:03Z")
I have nothing to offer. Wonder if the 2 amp is somewhere before the meter is hooked up is all. Thing is many times, whether over night going over and over something and then all of a sudden a light goes on (figuratively). Of course sometimes it never does which would lean toward your sister’s answer. I have been looking for my mason chisel for well over a year. Looked everywhere it should be. Didn’t need it and didn’t want to buy another. Even tried the prayer to St. Anthony a Catholic girl taught us once. Then a couple weeks ago I was rummaging through a drawer in my tool box looking for something else and there it was. My dad always blamed kids. I have no answer. St. Anthony is only for lost items. I don’t know who handles unsolvable problems. I still haven’t found my scratch awl though but bought another one. ---
**Author:** ![tcmichnorth](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/tcmichnorth/32/25126_2.png) [@tcmichnorth](https://community.cartalk.com/u/tcmichnorth)\ **Post date:** [December 3, 2021, 11:21am UTC](https://community.cartalk.com/t/stumped-to-this-point/180719/59 "2021-12-03T11:21:21Z")
> [@bing](#): > > Wonder if the 2 amp is somewhere before the meter is hooked up is all. This thought crossed my mind also. @ok4450 did you try looking for a draw with your other battery separately? You did say you used it in series. When a battery has dirt and crud on the top, it will create a circuit. I’m wondering if this kind of short can also be caused by some internal anomaly in the battery itself. I may be off the wall with this, but at this point I figure, off the wall suggestions might help. ---
**Author:** ![NYBo](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/nybo/32/17281_2.png) [@NYBo](https://community.cartalk.com/u/NYBo)\ **Post date:** [December 3, 2021, 4:14pm UTC](https://community.cartalk.com/t/stumped-to-this-point/180719/60 "2021-12-03T16:14:40Z")
Your sister may be on the right track. 👻 A battery cutoff switch may be your only path to sanity at this point. However, I know this mystery would continue to eat at me if this was my vehicle. ---
**Author:** ![ok4450](https://avatars.discourse-cdn.com/v4/letter/o/e9bcb4/32.png) [@ok4450](https://community.cartalk.com/u/ok4450)\ **Post date:** [December 3, 2021, 6:49pm UTC](https://community.cartalk.com/t/stumped-to-this-point/180719/61 "2021-12-03T18:49:23Z")
I checked the DERM module. Nothing going on there and yeah it has been downright frustrating. At this point I have to say it’s the worst electrical glitch I’ve ever had to wrestle. Truck started right up this morning. With the VOM connected/engine off the battery voltage is steady as a rock at 12.69 and not dropping one iota. I feel it can be driven anywhere, BUT the thought of being a 100 miles from home and the truck deciding to go stupid on me has me a bit hesitant. It’s not dying while running that is the problem; it’s the random not wanna start hiccup. I just cannot fathom how a 71 mA draw could sap 2 batteries with 1400 CCAs down into the 10 volt range in 2 hours. Both batteries work fine in other vehicles with zero issues. Pondering options; crusher or arson. Guess I could fill the gas tank and leave it running all the time with the doors locked… [Previous page](https://community.cartalk.com/t/stumped-to-this-point/180719.md?page=2) [Next page](https://community.cartalk.com/t/stumped-to-this-point/180719.md?page=4)