Battery draining

I posted on the Volvo forum, but its not as active
as this one, so I thought I would post here too.

Recent rebuild on this 85 Volvo 240 DL,
300000kms. Auto Trannie, B230F motor. Sedan. 3 spd trannie.

The battery goes dead after about 10 hours of not running. Put my
multimeter on it, when running the voltage is 14 volts, which rules out
the alternator. When not running, I can observe
the voltage dropping from 12.75 to about 12.30
or so. It may go lower, but this occured over
about a minute or so after the car was stopped.

Amperage drawn when the car is not running is
0.8 to 0.87 Amps, which shouldn't be enough to drain the battery in 10
hours. This was done
by removing the positive battery cable, and
putting my multimeter between the cable and
the positive post.

The battery is brand new, and I realize it could
be a dud. However, are there any other things
I should be checking? Cables appear to be in good
shape. The clamps on the posts are good too.

Thanks
t

 

Well, this is a honda group so this post really doesn't belong here but
there's no sense leaving you stranded since you are a regular poster, I
think. I've owned a volvo and know a little here and there about that car.

How about your keep the multimeter in line and pull one fuse at a time to
see what's causing the problem? One fuse should make it drop to near zero --
It will at least narrow it down because the problem could be anywhere. It is
not a dead short so most likely something is on that is normally off. (how
about the radio or final amplifier? - they are notorious for doing weird
things like this).
800 mA/hr is not normal and may get your battery drained sufficiently enough
to not start the next day.

Remco

 

Odd - I didn't see it on the Volvo forum (but I haven't been there this
evening - maybe in half an hour). No matter - the regulars there would tell
you the common sleeper here is the light inside the glove box. You can
remove the bulb to test that theory. If that fixes it, finagle with the door
to get it working right.

Mike

 

Thanks guys.

After taking all of your advice, we found nuthin!

BUT, there is this blade fuse in line with a wire
coming directly off of the positive terminal of
the battery. Apparently, it feeds the fuel pump
relay. Its a 30 Amp fuse.

Anyways, when I pulled that fuse, the draw on the
battery went from 0.87amps to 0.01amps. I'm
thinking my problem is there.

Any ideas on how to fix this? Once the power goes
to the relay, where would it go from there?

t

 

Occasional OT posts occur in other groups as well. Typically the poster has
not received a satisfactory answer in the proper group for his vehicle and
is posting in an OT group as a last resort.

An excellent group for posting fairly general questions (such as this) is
rec.autos.tech. There are quite a number of very knowledgeable posters
there, some of whom would be perfect to ask this question of.

That's the best way. An immediate drop upon pulling a fuse will reveal your
culprit. Remember to pull ALL the fuses and fusible links, including any
big fat ones that are bolted in (unless your culprit is flushed out early).

Is your alternator fused?

 

disallow wrote:

| BUT, there is this blade fuse in line with a wire
| coming directly off of the positive terminal of
| the battery. Apparently, it feeds the fuel pump
| relay. Its a 30 Amp fuse.
|
| Anyways, when I pulled that fuse, the draw on the
| battery went from 0.87amps to 0.01amps. I'm
| thinking my problem is there.

800mA certainly doesn't sound right for "idle current".

| Any ideas on how to fix this? Once the power goes
| to the relay, where would it go from there?

Don't know much (anything about Volvos, but on a regular Civic it would
go through the "main relay" into the ECU, which keep it at an open circuit
until it wants to power the fuel pump. You wouldn't happen to have any
schematics of any sort, would you?

I hope your fuel pump is not running 24/7? (or at least until the battery is
dead...)

A quick google shows that Volvo's of that generation have problems with wire
harnesses quite a bit (insulation eroding away? wtf?

http://personal.linkline.com/dbarton/WireHarnesses.html

 

you may a stuck or fused fuel pump relay which is also a common problem

 

Seems odd that they'd fuse a fuel pump with 30Amps and feed it directly off
the battery since a a fuel pump doesn't take very much power to run. Power
delivery (ie power drop across wires, requiring fat wires) is usually not a
problem.

My old volvo was an older model and don't remember if they had direct line
going to the pump.
What is more logical is that this fuses the alternator. An alternator is
usually directly connected to the battery. It does have diodes inside that
short and cause current to flow when it shouldn't. Can you follow that wire
to see where it goes?

Also, I'd imagine that if that fat wire and fuse indeed do feed the pump
through a relay, it would most likely be connected to the contact of the
relay (the switch side) -- there's no point connecting a high current wire
to the coil (actuator side) of the relay as that is definitely low current.
That being true, the only way that you can have any appreciable current
running is if the pump is running, even with the car shut off. That relay
must be driven somehow.

I'd still first check to make sure that that fat wire/fuse is not connected
to the alternator, though..

Remco

 

Just one more thought:

We know a car can't drive without a fuel pump but can drive without an
alternator (albeit not very long), right?
Disconnect that offending fuse and see if the car starts and runs. If it
does, that fuse was clearly not to the fuel pump.

Hope you find it soon. Let us know how you make out -- it might be OT but
now I am interested.

Remco

 

This particular question does get pretty model-specific, though. I have a
765T instead of a 240, but same year, engine (except the turbo version) and
tranny. One of the important issues regarding the mid-80s Volvos is that the
wiring was made in France and has a reputation for insulation crumbling.
I've heard it called "biodegradable" but I don't know if that was a design
thing or is an epithet. I have already replaced my engine harness but have
had to reinsulate dozens of other wires - and many of them can cause the
drain the OP experiences.

'disallow', since the fuel pump fuse seems to be carrying the current, have
you tried pulling the fuel pump relay to see if it disappears? I'm thinking
you may have a wiring short on the other side of one of the relay coils.
That is a lot of current for a fuel pump relay coil, but it sounds about
right for the in-tank pump, which is controlled by one part of that relay.

Mike

 

Nope - the fuse is for the fuel pumps. There is a small in-tank impeller
pump that draws a little under an amp and a main pump under the car below
the driver's seat that typically draws a bit under 10 amps... probably more
on startup. Both are controlled by separate sections of the fuel pump relay.
The in-tank pump is on any time the ignition is on, while the main pump is
timer controlled.

The alternator is not fused.

Mike

 

Yes indeed! The problem was with wiring starting sometime in the early 80s
and finally corrected by choosing a different supplier in 1988. My Volvo is
an '85 :-(

Affected wire, all the exposed small guage wire outside the passenger
compartment, will lose the insulation if touched. You have seen twigs where
the bark was just a loose crust on the wood? It's exactly like that.
Replacing the engine harness got rid of the majority of the affected wiring,
but I have already replaced or reinsulated dozens of feet of wire besides
that, including all the fuel pump wiring.

Mike

 

Yes, the wiring harnesses have a really bad reputation. Volvo went through
an exercise to remove all PVC plastics from their cars, and switched to
ABS. ABS has different properties,
yes it is more environmentally friendly. But I
gotta wonder, what has more impact, a wire harness
burning up, or junking an entire vehicle becuase
of a bad wire harness? Cuz I have seen a couple
volvos at the wrecker where thats all that
appears wrong with them. I guess it can get
pretty cost prohibitive to replace the harness
on an older vehicle, the harness for the 240 DL
was over $500 Canandian!

So the ECU wire harness was replaced. The Transmission CU wire harness
was not replaced,
but we did try to reinsulate all of the exposed
wires.

Thanks for the tips Mike. I will try to see
if the fuel pump relay is the culprit. If it
isn't then an examination of the wires after
the relay is in order.

I love this group, so many knowledgable people!

t

 

Just got this info from a guy on the Volvo
group, in case anyone is interested:

Mike F. Thornhill ON

 

14 V is a bit low. IIRC, my old Civics run 14.3 V, and that little
bit extra is critical to giving the battery a full charge.I run a 1 KW solar power set-up using a 24 V, 550 AH storage battery
as my main power source. Before putting a new battery into service,
it is essential to give it a proper initial charge, or service life
will suffer.

The voltage you measure suggests your new battery came to you
seriously self-discharged from sitting on the dealer's shelf. Since
it is probably sealed ("maintenance free"), I recommend using a "smart
charger" to prevent excessive gassing from overcharge, and possible
damage.

A properly charged battery may take overnight to drop to 12.6 volts
after the engine is shut off (charge terminated), if not loaded.

Back in the old days, when batteries had cell caps, I never saw a
"new" battery with more than 1/2 charge, specific gravity 1.215. Dry
charged must have a proper forming charge done on it, immediately, or
risk plate destruction due to a chemical process C&D Technologies (a
manufacturer of serious industrial and telephone batteries) calls
"hydration", white crystaline deposits on the plates.

I once monitored battery specific gravity on a new battery installed
without this initial bench-charge, relying on the alternator to bring
it up to full charge with "normal daily driving". Took a month. Not
good!

There is no "/hr" in the units for electrical current. "800 mA" is
correct.


Tom Willmon
near Mountainair, (mid) New Mexico, USA

Net-Tamer V 1.12.0 - Registered

 

Wow - a fat lead going to the fuel pump -- imagine that...
Maybe this they are using the type of pump that you can also clear a
port-a-potty with

Scratch what I said in my previous two posts.

 

Wow - a fat lead going to the fuel pump -- imagine that...
Maybe this they are using the type of pump that you can also clear a
port-a-potty with

Scratch what I said in my previous two posts.

 

lol, well its a volvo, so who the hell knows?!?

Very Funny!
t

 

Thanks for the info Tom.

This was a Motomaster Eliminator from Canadian
Tire up here in Canada. They are notorious for
being of low quality. I also have one for my 98
civic, and I have to say I am not impressed, I
will probably go for a Honda OEM battery next
time, my original lasted over 8 years!

However, it is not a maintenance free battery.
I pulled the caps off, just to make sure the
water level was good, but did not perform any
other tests on the electrolytes.

So the big question here, is 800mA enough to
drain a battery over night, or a couple days?

Terry

 

Yeah, Volvos are quirky cars -- I had a 1972 145E, I guess their first
entry in the fuel injected market. Have worked on some DLs friends
owned. Built like a tank, that much is sure.

I've owned two 900 Saabs (the other Swede) as well -- talk about
quirky!! They are great fun to drive but do have some not so
straightforward issues when it comes to repair.

Hope you got it resolved?
Remco