Battery Drain

[Adam]

I bought an old 1990 Winnebago Warrior this summer and have been fixing it up so that it is will be "road worthy" . . . this process has gone fairly well, but now I'm dealing with a phantom battery drain issue . . . the multi-meter shows a drain of 1.42 on the engine battery when the ignition is off . . .  I have checked the obvious things (switches, lights, etc.)    Any suggestions?  (The battery is new and tested OK).  I put a "kill-switch" on the battery for now, until I can locate the problem . . . the battery does not lose voltage when disconnected.   Engine battery charges when running the RV down the road . . .  just can't let it "sit" with the battery connected.   My hopes are that someone has hit this bump in the road with this particular model and found the "fix".   It's a Ford chassis . . . 

[DesertMiner]

Radio?  Controllers?  Leaking to coach batteries?  Solenoids?

[Adam]

In that, I don't have an adequate working knowledge of electrical matters, I can't say . . . I did "take a shot" and changed out one of the solenoids with a new continuous 200 amp solenoid (the one closest to the engine battery) . . . and cleaned up the terminals and cables to the other one on the firewall . . . just to see. 

Radio seems to be off until I turn on the ignition . . . then it lights up.

I have not checked to see if it's leaking to the coach batteries (2) . . .  I would need some guidance.

(What are controllers used for?)

 

[sandsys]

3 hours ago, Adam said:

Radio seems to be off until I turn on the ignition . . . then it lights up.

I don't speak electronics so this may be a stupid suggestion but "seems to be" makes me nervous. Why not just turn off the radio just in case it's in standby mode thereby using power?

Linda

[Adam]

Thanks Linda . . . I do keep the radio off . . . it lights up when I turn on the key, even when it is off.   When I pulled the fuse to the circuit with the radio, I still had the phantom drain.     

[Kirk W]

First, welcome to the Escapee forums! We will do all that we can to assist you so don't hesitate to ask.

Parasitic battery losses were very common in the older RVs so your problem is not unique. It might be helpful to know what chassis your Winnebago rides on as there are some differences. 

10 hours ago, Adam said:

. . the multi-meter shows a drain of 1.42 on the engine battery when the ignition is off . . .

Are you seeing a 1.42a current with an amp meter in series with the battery cable? The best way to measure is to set the meter on amps, then lift one battery cable and put the meter between the battery cable and the battery post. I highly doubt that the radio is drawing that much if it is turned off. With the meter installed you should start removing fuses one at a time to see if the meter changes. The problem could be several small loads. 

10 hours ago, Adam said:

I have not checked to see if it's leaking to the coach batteries (2) . . .  I would need some guidance.

There should be a solenoid between the coach batteries and the chassis battery that opens when the engine is turned off but typically has an emergency start switch to close it if you wish to jump-start the coach from the coach batteries. When working properly it will be open if the engine is not running so that the two systems are isolated. Since you have acknowledged that you know little about this system, may I suggest that before you spend a lot of money throwing parts at it, you would do well to read Mark Nemeth's The 12 Volt Side of Life, parts 1 and 2? There are several of us on the forum with extensive electrical & RV backgrounds but we can help much more if you have some grasp of what is in the system and how it should work. 

[Adam]

Thanks Kirk . . . I'll read this article . . . I'll get back with you later today . . . 

[Adam]

Thanks Kirk . . . I'll read this article . . . I'll get back with you later today . . .  

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Good article . . . (I noticed that you may have been a sub sailor, which explains your familiarization with batteries, i.e. Gould 53A).

When I put a meter on the house batteries, my observation is that the reading is 13.65 . . . and when I check the engine battery, it is normally 12.65 . . . 

When testing the circuits with the ground cable disconnected, I get a reading of -2.20  . . . when I pull the fuses, on one circuit, it drops to -1.42. 

[beemergary]

10 hours ago, sandsys said:

I don't speak electronics so this may be a stupid suggestion but "seems to be" makes me nervous. Why not just turn off the radio just in case it's in standby mode thereby using power?

Linda

Some aftermarket radio's with a Clock will drain your battery. Been there.

[beemergary]

I 'd eliminate the coach side of system. Check wires connections for dirt-oil-moisture and rubbing something that is grounded. If you disconnect a wire and reconnect and it sparks you have draw in the system. People will laugh but lots of electrical and ignition (with engine running) problems can be found in the dark.

 

[Kirk W]

2 hours ago, Adam said:

When I put a meter on the house batteries, my observation is that the reading is 13.65 . . . and when I check the engine battery, it is normally 12.65 . . . 

Was your RV connected to shore power when you measured the battery voltage? It sounds like it probably was since the typical 12V power from a converter is about 13.5 - 13.7v  when neither under any charge or discharge. This also means that your chassis battery is very close to what it should be and is reasonable for a battery that is not new.

2 hours ago, Adam said:

When testing the circuits with the ground cable disconnected, I get a reading of 2.20 (ohms) . . . when I pull the fuses, on one circuit, it drops to 1.42. 

I'm not really sure what this may mean? Where were you measuring between? If you measure between a circuit and ground it is impossible to know what value in ohms is proper without knowing a lot about what is in the circuit. A motor or solenoid will measure close to 0 ohms when no power is applied. A heating element is typically between 50 & 100 Ω. While series loads add those in parallel divide so with multiple circuits from one fuse will have a very low resistance. About all that measuring an unknown circuit to ground can tell you is that if it reads 0Ω it is suspect to be shorted.

[Adam]

Kirk, I measured from the negative battery post to the negative battery cable after I removed the battery cable.  The amp draw is 2.20 . . . when the ignition is off.   Should not have said ohms.

 

[DesertMiner]

 

[Kirk W]

20 minutes ago, Adam said:

The amp draw is 2.20 . . . when the ignition is off. 

Good! The drop to 1.42 means that whatever was on the removed fuses draws .78a which is enough to be noticed over time but it also means that you have Some load of 1.42a that does not pass through your fuse panel. With RVs, and especially with early ones, it is not uncommon for things to have been added in with an in-line fuse holder that bypass the main fuse block. I would look for extra wires that connect either to the battery post or to some terminal between the battery and the fuse panel. One thing commonly wired around the fuse block is an electric step if you have one. It is sometimes done so that the step will work even if you have a battery isolator that is open. The step usually is supplied by the chassis battery to enable the use of it when the coach battery is out of service. In some cases, the step can draw power from either battery. 

When we had our 1987 Allegro, I found that it had several parasitic loads that I was never able to pin down and so would run the chassis battery down in about a week. What I did was to install one of the knife type battery isolators between the negative post and chassis ground and just open it every time we stopped for longer than a night or two. 

[Adam]

Thanks Kirk . . . you are so helpful . . . We are headed to Edisto Beach, SC and I will have an opportunity to look for something added on with an inline fuse . . . I remember seeing one . . .

Yes!  I did buy the knife type battery isolator several days ago and installed it . . . I can see a big difference already. 

Ready for a shakedown cruise!   I'll let you know how it goes.

[Adam]

Well the shakedown cruise was a bust . . . whenever I turned off the engine . . . even after 34 miles to gas up, my rig did not want to start . . . finally did (with help from the generator and a battery charger) . . . then later in the day, I inadvertently shut off the engine . . . same thing . . . did manage to get to my destination.   A week later, when driving home, I resolved to leave the engine running all the way home (400+ miles).  To no avail . . . I lost power going down a mountain (whee)!   Switched out the battery and drove the rest of the way home (2 1/2 hours).  

So . . . . the next day, I resolved to isolate the house batteries from the engine battery . . . Voila!   No phantom drain!  I've checked and double-checked the (new) chassis battery . . . no drop in voltage.  I'm going to take the old battery to Walmart and see if that was the problem.  (I would like to know for sure what the deal was.)  

Happy to see the engine battery maintain its' charge . . . but puzzled why it is still hard to crank after it warms up . . . going to change out the starter . . .

Thanking the good Lord to get home safely!

[sandsys]

I'm also glad you are home safe. If you ever find the cause, it would be good to post it here.

Linda Sand

[Kirk W]

10 hours ago, Adam said:

A week later, when driving home, I resolved to leave the engine running all the way home (400+ miles).  To no avail . . .

If you lost power with the engine running the alternator must not be working??  

[Adam]

I will have that checked (again).    Hopefully, the hardest part is behind me . . . checked the battery last night and it is holding a charge!  Wish me well.

[Adam]

 I did not need to replace the starter . . .  I took some insulation (fiberglass and wrapped it around the starter to ward off heat from the adjacent header and exhaust pipe.  After running it for approx 20-30 minutes, I turned off the engine and restarted it with ease!  Twice!    In all my life, I never realized that heat will affect the windings in your starter!   I'm elated!!!  Part of the learning curve. 

[beemergary]

52 minutes ago, Adam said:

 I did not need to replace the starter . . .  I took some insulation (fiberglass and wrapped it around the starter to ward off heat from the adjacent header and exhaust pipe.  After running it for approx 20-30 minutes, I turned off the engine and restarted it with ease!  Twice!    In all my life, I never realized that heat will affect the windings in your starter!   I'm elated!!!  Part of the learning curve. 

Musta never owned an older Pontiac. Gas engines can also vapor lock and turn over hard making you think battery or starter. Those mini reduction starters work great.

[Adam]

I'm hoping that in the near future that the learning curve isn't so difficult!  🙂

 

 

[Kirk W]

14 hours ago, Adam said:

In all my life, I never realized that heat will affect the windings in your starter!

The GM P-30 series chassis of the late 80's and 90's was well known for what was called "hot starter syndrome" where it would start find when cool but not start when hot. Eventually, those cooked starters would fail completely but a heat shield usually resolved the issue.