Interstate Maintenance & Upkeep

[InterBlog]

Originally Posted by Boxster1971

OK - right, if its bluetooth then not powered when the key is off.

Now I have to refresh my memory as to what voltages I should be on the look-out for. Specifically I need to define the safe voltage floor.

Engine running, fully charged new battery = around 12.8, is what the OBD is showing.

Sprinter Forum says that if something goes wrong, the engine will continue to run down to about 10.5, but it certainly won't re-start. Other threads cite 11.8 as being too low to re-start. I need to determine what the "panic button" voltage is.

[DogMobile1]

Since you are such seasoned travelers I hope you will forgive this butting into your thread with an unrelated question.....but as a newbie I could use your help. Here goes....its a battery question for 2012 airstream interstate. Is it ok to leave connected to shore power while stored for an extended time or should we use trickle charger. And should main battery disconnect switch ( under our bench seat) be on or off? I will be seriously grateful for any advise,. Thx

[gmillerok1]

If your 2012 has the Magnum MS1012 inverter charger, which has a (very) smart charger leave it plugged in, and I, at least, leave the battery disconnect switch on, since it is plugged in. The charger will keep the house batteries charged while in storage and will float them when they reach full capacity.

On the other hand, if it has the Tripplite 750, remove it and replace it with the Magnum MS1012. Or don't leave it plugged in. I'd get a trickle charger in that case. The Tripplite will cook your batteries and ruin them as the charger is a very poor one indeed.

I think Airstream made a change from one to the other mid-year in 2012 so I don't know what yours had installed. My 2011 had the Tripplite whiich I replaced long ago with Magnum.

[Lotus54]

Originally Posted by InterBlog

Now I have to refresh my memory as to what voltages I should be on the look-out for. Specifically I need to define the safe voltage floor.

Engine running, fully charged new battery = around 12.8, is what the OBD is showing.

That is low.
With the engine running, it should be closer to 14V certainly over 13V.

The first pic is a general battery state of charge.
The second is from the MB service manual.
Last is the engine off current draw specs.

Even with a fully charged battery every vehicle I’ve ever tested has higher charge voltage when running.
Of course, I would check with a voltmeter on the battery itself to verify things are correct.
I would also suggest using a good clamp ammeter (with very low range) and check the current draw with everything off. Just the earth side cable (s) may Be the easiest.

[wachuko]

Did you see my post on the battery cable?. Common issue... not sure if you have updated that cable already.

Infamous Y cable from starter to battery.

And I too see 14.1 at batteries when engine is running...

[Tincampers]

That was so easy, a caveman could do it. Took about 45 minutes including the warm up.

[wachuko]

Originally Posted by Tincampers

That was so easy, a caveman could do it. Took about 45 minutes including the warm up.

“I am offended by that comment”

[Tincampers]

Originally Posted by wachuko

“I am offended by that comment”

Get over it caveman!

[Boxster1971]

Originally Posted by InterBlog

Now I have to refresh my memory as to what voltages I should be on the look-out for. Specifically I need to define the safe voltage floor.



Engine running, fully charged new battery = around 12.8, is what the OBD is showing.



Sprinter Forum says that if something goes wrong, the engine will continue to run down to about 10.5, but it certainly won't re-start. Other threads cite 11.8 as being too low to re-start. I need to determine what the "panic button" voltage is.

If you are only seeing 12.8 volts from the OBD port with engine running you have a charging system problem. That ultimately may have caused your dead battery.

As others have mentioned 14 volts is normal. I see a range from 13.8 to 14.2 on my Ultra-Gauge.

[rmkrum]

13.8 to 14.2 with engine running at idle is what you should see on pretty much ANY vehicle at the battery terminals.

[toskeysam]

Well “CRUD!”........ I had a bad water leak in street side window behind the driver. Took it to Jackson Center in early June. They pulled the window out, cleaned it all up, reset the window and leak checked. Since then, we have had nothing but hot dry weather, until today....lots of rain. Went out a few minutes ago, just to check it out.......#&$@....wall is wet again. I have been all over the roof, anything that looked “less than stellar” was removed and replaced with new Sikaflex.... I am stumped! Not to mention totally p____d off. I’m pulling the wall out, somehow. It’s ruined at this point so my damage will be inconsequential. Looks like I’m going to have to figure out how to remove that gray trim on drivers pillar after all

[InterBlog]

Apparently the OBD is a lying sack of ****. I don't know why this is the case. Maybe there's a way to calibrate it.

Simultaneous readings, engine running.

[LB_3]

Originally Posted by InterBlog

It's called OBD Fusion and it bluetooths to my phone. I looked for a model number just now but I can't find an "About" page. LB_3 chose it.

It's a little thing that remains plugged in 100% of the time. I don't think it's powered when the key is off. It's been there for a couple of years with no problems.

IIRC, I had to pay an extra ten bucks to put the app on my phone, so that we each have it.

OBD ports have continuous power so the Bluetooth module is always powered. We should probably unplug it for long term storage since I don’t know if it turns itself off.

The OBD Bluetooth device is by Carista: https://www.amazon.com/dp/B00YVHGTBM..._N6avBbDAAM7ZT

The iPhone app is called OBD Fusion. For years Apple kept s tight kid on approved Bluetooth protocols so the only options were wifi OBD scanners. That’s no good at home on the iPad when I need the WiFi to look up codes and YouTube videos. There may be better apps but that was the first one with Bluetooth .

[Tincampers]

Originally Posted by InterBlog

Apparently the OBD is a lying sack of ****. I don't know why this is the case. Maybe there's a way to calibrate it.

Simultaneous readings, engine running.

Engine running, those readings on the battery are most likely from the alternator. To truly test the battery, disconnect it from the vehicle.

[InterBlog]

Originally Posted by LB_3

OBD ports have continuous power so the Bluetooth module is always powered. We should probably unplug it for long term storage since I don’t know if it turns itself off. .....

The light really does go out when the refrigerator door is shut. In other words, the OBD's LED glow ceases when the engine is turned off. I checked.

And the iPhone won't interface with it when the engine is off. So if it IS still powered, it's not drawing at full juice.

Edit: As I mentioned above, the OBD has been in place for what, at least two years? And we've never even remotely had a battery problem before now.

Edit II: We could have an alternator problem. The alternator is only a year old - it's the upgraded one ($$$) that LB_3 installed to deliver more juice to the lithium battery. We have gone probably 8,000 miles on it with no issues.

My weak and anecdotal understanding is that, when alternators go, they go pretty fast. Writer Brent Rose, who has been living in a T1N for the past 3 years, has lost two of them. They both went so suddenly that they left him at a standstill in the middle of the freeway. In other words, his rig started up just fine but then by the time he got a few miles down the road, it was all over. I don't know if that kind of failure is obligatory for alternators, though.

[wachuko]

I keep posting the reference to the Y cable. Did you update/replaced that cable? A lot of the symptoms you are describing match that of a failing Y cable.

[rmkrum]

Alternators don’t have brushes like the old generators. But, they do have slip rings and carbon, spring loaded brushes that ride on them to provide power from the regulator to the rotor windings. The brushes wear very slowly, but when they wear too short, the alternator instantly quits, and your battery dies real fast in a modern car.
Had it happen to our old Volvo. Had to disassemble the alternator on the road and notch a plastic part to get a couple thousandths of an inch of brush travel to get home. Another reason to carry a Swiss Army knife. McGyver would have been proud. The kids were gobsmacked at that trick by daddy...
Alternator ran another couple months until my mechanic rebuilt the alternator.

[InterBlog]

Originally Posted by wachuko

I keep posting the reference to the Y cable. Did you update/replaced that cable? A lot of the symptoms you are describing match that of a failing Y cable.

Can you define the part name or number more closely?

I asked about it at O'Reilly's and they didn't understand the reference. Neither does LB_3.

Thanks.

[wachuko]

Cable that goes from the Alternator to the Starter to the Battery... has an inline resistor that degrades over time.

https://www.factorychryslerparts.com...8087502AA.html

Could it be that it was not there for 2006 Sprinters? EDIT: That might be the case... looks like only for 2007 and newer... apologies for the incorrect suggestion...

A lot of information in the Sprinter forum. Here:

https://sprinter-source.com/forum/sh...ad.php?t=39438

Part number:

Video:

https://www.youtube.com/watch?v=am_uD3rXl6s

[LB_3]

I was thinking of replacing the alternator cable. Looks like it also goes to the starter (thus the Y name). I guess that's next.