Bizarre battery behavior

[icarp]

Originally Posted by Jonny H

Meanwhile I have had an Odyssey PCA925 (28Ah) in my car for 4 years now. My car has electric AC and (prototype) electric heat so is under a constant load of at least 60A every time I drive it. Have never had the battery drain and have never used a trickle charger.

How? I have a decent modern alternator (one of our 175A units). QED

Johnny , I think there are a few Odyssey batteries out there that work .
I taught the SPECIAL FORCES for 17 years, this battery was invented and produced for them . In the beginning they were great . In the last 5 years they have lost any and all quality control , in the toilet as far as I am concerned . This idea that a battery will not accept a charge when it needs a charge is nuts .
THE FACT THAT YOU HAVE TO TRICK IT with another charged battery in line just to add amps is also nuts .
Battery mfg is just a racquet to steel money . In 1978 you could buy a lead acid battery from sears , called a DIE HARD and get 10 years of use out of every one .

I am not aware of one single battery made today that can do that .

I am not mad at you , just mad at the industry that is perpetrating the fleecing of all customers world wide

Please forgive the RANT

Ian Carpenter

[Jeff Higgins]

Originally Posted by jwakil

I'm also suspicious of the battery but I thought the AGMs were the best non-lithium batteries you could buy. I'm a little weary of going to Lithium just due to the unknowns and requiring different trickle charger and if it can be jump started in emergency with regular battery, etc.

Having actually used lithium batteries, I am a bit more than just leery of them - I won't go back to them. Too many downsides to justify the weight savings. I'll stick with AGM or lead acid.

Originally Posted by Jonny H

Meanwhile I have had an Odyssey PCA925 (28Ah) in my car for 4 years now. My car has electric AC and (prototype) electric heat so is under a constant load of at least 60A every time I drive it. Have never had the battery drain and have never used a trickle charger.

How? I have a decent modern alternator (one of our 175A units). QED

My first 925 went over ten years absolutely hassle free. Its replacement, another 925, is now over five years old and has given me no trouble whatsoever. Both of my sons run them as well, one in his '68, the other in his '79. I went with suitable Odyssey batteries in my motorcycles after having tired of the lithium games I had to play. Never a problem with the Odyssey AGM's. Oh, and plenty of cold cranking power on a couple on sometimes recalcitrant, highly modified 11:1 compression motors, the 3.0 in my '72 and my '93 Ducati Super Sport.

[COL911]

“The normal sequence is I turn the key and the light comes on and stays on after car is started. I hit the gas and after about 2000RPM the light will go off and then I see the voltage climb to 14V so I know alternator is activated. This is how it’s been since I’ve owned the car for 10yrs. However, the time in question I jump started the car, no lights came on and the voltage stayed at ~9V even after I revved the engine, so clearly the alternator was not activated. Also none of the dash gages were working.”

I’m pretty sure that alt dash light should turn off as soon, or within seconds of the engine firing. There should be no need to blip the throttle, so I wouldn’t exclude alt or voltage regulator just yet.

[jwakil]

Originally Posted by COL911

“The normal sequence is I turn the key and the light comes on and stays on after car is started. I hit the gas and after about 2000RPM the light will go off and then I see the voltage climb to 14V so I know alternator is activated. This is how it’s been since I’ve owned the car for 10yrs. However, the time in question I jump started the car, no lights came on and the voltage stayed at ~9V even after I revved the engine, so clearly the alternator was not activated. Also none of the dash gages were working.”

I’m pretty sure that alt dash light should turn off as soon, or within seconds of the engine firing. There should be no need to blip the throttle, so I wouldn’t exclude alt or voltage regulator just yet.

I believe I’ve seen the alternator needing to to exceed a certain rpm at startup for it to be activated on some other vehicles as well. After I blip the throttle and the Voltage goes up, then it will still be above 13.5 even after rpm’s drop to idle. And like I said this has been the normal process since I’ve owned the car (10+ yrs) and the previous owner told that was normal for the car.

[jwakil]

Ok, after further investigation, I believe I have found the problem. I have some power draw in fuse 4, which supposedly feeds the interior lights and radio. When I disconnect this fuse, the battery does not drain even after multiple days of sitting. Now when I park in the garage I just take out fuse 4. However, I cannot figure out exactly what the power draw is. None of the interior lights are on, and radio is also off. Clock is removed. Any likely culprit?

[dg567]

Aftermarket radio?

[jwakil]

Originally Posted by dg567

Aftermarket radio?

Yes its an aftermarket radio but it's the same one for many years and didn't have this problem till recently.

[stownsen914]

Wiring can be such a pain. Might be worth trying to trace the wiring to see what's actually on that fuse.

[darrin]

Originally Posted by jwakil

Ok, after further investigation, I believe I have found the problem. I have some power draw in fuse 4, which supposedly feeds the interior lights and radio. When I disconnect this fuse, the battery does not drain even after multiple days of sitting. Now when I park in the garage I just take out fuse 4. However, I cannot figure out exactly what the power draw is. None of the interior lights are on, and radio is also off. Clock is removed. Any likely culprit?

Jwakil -- does your driver's side dome light switch work (ie. does the interior dome light come on when you open the driver's door and go off when you close it)? On my '86, there's a relay that's activated when the engine's turned off that allows one to continue to operate the power windows until a door's opened (and uses the dome light switch to trigger door closed state). A failed dome light switch caused this relay to remain activated (and continue to draw current) indefinitely -- this would drain my battery in about a week. Easy to check by seeing if your power windows continue to operate after opening a door and/or seeing if your dome light operates as normal (turns on with door opened, etc.). -- replacing my dome light switch resolved this issue for me

[jwakil]

Originally Posted by darrin

Jwakil -- does your driver's side dome light switch work (ie. does the interior dome light come on when you open the driver's door and go off when you close it)? On my '86, there's a relay that's activated when the engine's turned off that allows one to continue to operate the power windows until a door's opened (and uses the dome light switch to trigger door closed state). A failed dome light switch caused this relay to remain activated (and continue to draw current) indefinitely -- this would drain my battery in about a week. Easy to check by seeing if your power windows continue to operate after opening a door and/or seeing if your dome light operates as normal (turns on with door opened, etc.). -- replacing my dome light switch resolved this issue for me

My dome light seems to work normally with drivers door but have noticed that the passenger door doesn’t trigger it always. Sometimes I have to wait a long time or I wiggle the switch by hand to set it free. However I don’t believe I’ve ever been able to roll windows down with the key off, so I’m not sure my 81’ has the same relay and feature. But I’ll double check.

[LJ851]

Originally Posted by icarp

Johnny , I think there are a few Odyssey batteries out there that work .
I taught the SPECIAL FORCES for 17 years, this battery was invented and produced for them . In the beginning they were great . In the last 5 years they have lost any and all quality control , in the toilet as far as I am concerned . This idea that a battery will not accept a charge when it needs a charge is nuts .
THE FACT THAT YOU HAVE TO TRICK IT with another charged battery in line just to add amps is also nuts .
Battery mfg is just a racquet to steel money . In 1978 you could buy a lead acid battery from sears , called a DIE HARD and get 10 years of use out of every one .

I am not aware of one single battery made today that can do that .

I am not mad at you , just mad at the industry that is perpetrating the fleecing of all customers world wide

Please forgive the RANT

Ian Carpenter

I’ve been using conventional Interstate batteries in all my cars for a few decades now. The last 4 of them (just replaced one) have lasted 9-10 years.

[darrin]

Originally Posted by jwakil

My dome light seems to work normally with drivers door but have noticed that the passenger door doesn’t trigger it always. Sometimes I have to wait a long time or I wiggle the switch by hand to set it free. However I don’t believe I’ve ever been able to roll windows down with the key off, so I’m not sure my 81’ has the same relay and feature. But I’ll double check.

If windows don't work with key off/door open, then doesn't seem this would be the source of your problem

[dg567]

Why not disconnect the radio and see if the draw persists? Could be a faulty radio.

[RDM]

I believe the frequency valve relay under the passenger seat is a) on this circuit and b) always powered, at least if your '81 is like my '80. I had this problem, and a new relay fixed it.

[Tea Tray]

To test for a “off condition” current draw, disconnect a battery terminal and connect a test light across the post and terminal. I use an incandescent type light.
If there is a draw the light will come on.
Pull your fuses one by one. When the light goes out, you found the circuit.
On my ‘87 3.2, there are several large wires hooked to the positive battery post.
Use the same technique on each of the big wires

[PeteKz]

+1 on previous suggestion: Disconnect the battery and let it sit for a couple weeks. If it stays fully charged and can start the car easily, then rule it out. Look for a parasitic drain or poor charging.

[M491Cabriolet]

Originally Posted by Tea Tray

To test for a “off condition” current draw, disconnect a battery terminal and connect a test light across the post and terminal. I use an incandescent type light.
If there is a draw the light will come on.
Pull your fuses one by one. When the light goes out, you found the circuit.
On my ‘87 3.2, there are several large wires hooked to the positive battery post.
Use the same technique on each of the big wires

I have a similar problem as the OP, but my car is a LWB model, so no power anything. I was hoping someone could tell me how to set up the incandescent bulb between the battery terminal and battery post to test individual fuses.

Does anyone have a picture of how you set this up? If not, a thousand words would be helpful! Thanks.

[darrin]

Originally Posted by M491Cabriolet

I have a similar problem as the OP, but my car is a LWB model, so no power anything. I was hoping someone could tell me how to set up the incandescent bulb between the battery terminal and battery post to test individual fuses.

Does anyone have a picture of how you set this up? If not, a thousand words would be helpful! Thanks.

M491Cabriolet -- if you started with a 12v light bulb in a socket with two wires coming out of it, you'd a) confirm the light works by touching one wire to each battery terminal (this would power the light with 12v and cause it to light up) after disconnecting the light from the battery, you'd then b) disconnect the negative battery cable from the battery terminal and then c) attach one of the two wires to the battery's negative terminal and the other to the negative battery cable. This would cause the battery's current to run through the lightbulb. Parasitic drain would cause the bulb to light up -- no drain (no completed circuit) would cause the light to turn off.

[M491Cabriolet]

Thanks for that!