Slow battery drain in a 88 Accord LXi

[GooperMC]

I posted this at www.honda-tech.com and someone there suggested that this forum might be able to better help me.

Here is the background:
About 3 weeks ago my car started dumping coolant, which I tracked down to a leaky heater hose. Lacking a garage to do any real work (and the damn hose was in the back under way too much stuff) I brought my car into the shop. The mechanic replaced the hose was as well as my valve cover gaskets. When I came to pick up the car the mechanic also told me that my battery was dead and negative lead was broken. The battery was only 3 years old and I hadn't had any trouble with it up to that point. The battery was under warranty so the mechanic replaced it and soldered on a new negative lead.

I drove the car for a few days and it was fine and then didn’t drive again for 2 weeks. I went on vacation and when I got back the brand new battery was dead. I had no dome light, no radio, it was dead. I was able to jump the car and the alternator charged the battery (I was able to start the car again after driving around for about 15 minutes), however the next day the battery was dead again.

Here is what I have done as diagnostics:
I attached a voltmeter in series to my battery. When nothing is on, my car is drawing about 250mA. That seemed high to me so I opened the fuse box and started pulling fuses. After I pulled the "hazard" fuse my car was only pulling 15ish mA (I don't remember the exact number), and no other fuses made a major difference.

I replaced the hazard fuse and went through the fuse box next to the driver’s seat; however none of these fuses dropped the current. I then went through and disconnected all the lights that go on when the hazards are on, the 2 taillights, the 2 in the front, and the 2 on the sides of the car. I was hoping that there was a short in one of the sockets but disconnecting all the lights didn't make a difference. Just for kicks and giggles I also disconnected my trunk light and my glove box light which also didn't make a difference.

I have also testing the battery voltage while the car is running, it about 14V, so I think that the alternator is working.

After doing a little research online I learned that the solid state memory for the cars chip is also on that circuit which scares me a little.

I have two questions:
1) Does anyone know of anything else that is on the “hazard” circuit?
2) Does anyone have any idea of where the short could be, or at least know of more diagnostics that I can do to narrow it down?

General Info about my car:
It is an 88 Honda accord LXi that my family has had for about 4 years. It has 120,000 miles on it and is in pretty good shape. In the 4 years my family has had the car is has only required minor work and none of that work has been in the electrical / charging system.

Thanks in advance and you are going to have to bear with me, I really don't know that much about cars (I just have smart friends and know where to look for information).

[Moodybluesr]

The FSM says that the hazard fuse supplies power to the: hazard lights/relay, side marker lights, integrated control unit

I would try unplugging the Hazard relay to see if that drops your drain. It is located on the back of the under-dash fuse box.

If that doesn't solve it, try unplugging the ICU. This is a black box located behind the storage space/cd player/cupholder (depending what you have) about 5x3x1 inches that controls various electronic functions on the dash (oil pressure alarm, seatbelt and key alarms, headlight alarm, key light timer, side markler flasher relay). If that appears to be the cause there is a several page illustrated input test that you can follow in the FSM (if you have one). Hope this helps.

[HondaBoy]

just some random stuff, but my power lock controler had gone out and was draining the battery until we unplugged it. that's under the front passenger seat. anyway, i've replaced it not too long ago, no battery drains. how about the rear defroster switch, i've heard that can be a problem on our cars to drain the battery.

[GooperMC]

Moodybluesr,

Thanks for the reply. I have already checked the hazard relay it was one of the things that I did while fiddling with the under dash fuse box.

I will check the ICU next.

Hondaboy,

Wouldn't the power lock controller / rear defroster switch not be on the hazard circuit?

Thanks again.

[HondaBoy]

no, but those are some things that trick people when they check the systems. just the fact that other people i have know had the same defroster draining the battery, but the lock controller, that was my problem, its not that hard to unplug and plug back in either doesnt require taking the seat out.

[Moodybluesr]

He has already traced the drain to the hazard circuit, thus eliminating the need to check unrelated (ie. power window, defroster) circuits.

[GooperMC]

Moodybluesr you were spot on it was my ICU.

A few questions
1) How much would it cost to replace the entire unit, I am assuming it will cost a lot?
2) I am not in possession of FSM (assuming this is a Factory Service Manual). Where can I pick one up and how much will it cost?
3) Is there any way that I can get thoses test w/o a FSM?

Thanks again you are my hero.

['89AccordLX(Rus)]

Visit http://www.pauldesign.ru/ and download the Shop Manual. It will tell you everything you want to know.

[Oldblueaccord]

250 millamps doesnt sound real high to me. I think my car will run down in two weeks time . Sure you weren't checking voltage most multi meters wont do amps less you spend some $$ on one.

Normal car batteries might handle 2-3 total drain downs before there crap. Since its new it should have a warrenty. My batteries here in the south last about 3 years. I think its the heat plus our charging systems run about 14v which is a little high.

Im testing out a Optima yellow in my truck see how they hold up.


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[AZmike]

Moodybluesr you were spot on it was my ICU.

A few questions
1) How much would it cost to replace the entire unit, I am assuming it will cost a lot?
2) I am not in possession of FSM (assuming this is a Factory Service Manual). Where can I pick one up and how much will it cost?
3) Is there any way that I can get thoses test w/o a FSM?

Thanks again you are my hero.

I bet you could get another one for $5 at a cheap junkyard. It's not a common problem so any other part should be fine. Someone on the board might be willing to send you a spare out of a parts car for a few dollars if you're not close to any salvage yards.

You could buy your own factory manual for about $60 + s/h from www.helminc.com. It was worth it to me to have a hard copy.

[Moodybluesr]

A reply to your questions in order:

1) I assume that the ICU would be quite a bit of $$ from the dealer, but it would probably be dirt cheap from a junkyard... or just make a post in the "wanted" section on this board. It is a small item and shipping would be cheap at least.

2) I got my FSM by watching eBay (I think I paid around $15 shipped). This will require you to watch and wait of course. Here's one:
eBay 1988 Accord FSM
or you could opt to buy a new one from Helms:
New Helms Accord FSM

3) Unfortunately I don't have a scanner; if you find someone with a scanner and the FSM they need to scan pages 25-101 through 25-103 for the testing procedures. Your drain could be a faulty ICU, but it could just as easily lie in on of the circuits related to the ICU.

[GooperMC]

I do have a local junkyard so I'm betting that I can get it from there. However if I can't does anyone see anything wrong with just disconnecting it? According to the FSM this thing controls:
- Brake light circuit failure sensor
- Day-time running light relay
- Seat belt time

Seems like I could just disconnect this and be OK.

[AccordEpicenter]

oh yea... 250ma is alot for the car to be sitting with no lights on/everything off/key out/door closed. It should be around 10-15ma at max

[GooperMC]

I do have a local junkyard so I'm betting that I can get it from there. However if I can't does anyone see anything wrong with just disconnecting it? According to the FSM this thing controls:
- Brake light circuit failure sensor
- Day-time running light relay
- Seat belt time

Seems like I could just disconnect this and be OK.

I take that back I am a litte confused about the FSM that I downloaded from that link 89AccordLX(Rus) gave. All I see is a 86 manual and an 88 supliment. The 88 supliment doesn't have a section for electrical and what I have doesn't match the pins in the 86 manual.

What I have has 2 rows of 9 pins. The top row is 3 pins with 2 blanks and 4 more pins. The bottom row is 9 solid pins.
Here is bad ascii art. The - are pins and the E are empty.
---EE----
---------

Help please.

[Moodybluesr]

I listed what the ICU does in my first post; I would be a little bit concerned about getting rid of the oil pressure light. Without it you will have no early warning for a potential major engine problem. The sidemarker flasher relay is also on the same circuit. Do your turn signals work when you unplug the ICU?

[GooperMC]

Moodybluesr: you are probably right about the oil pressure light. I would feel real stupid if I seized my engine because I didn't fix this. You are also right that the side turn signals don’t work when I unplug the ICU (probably don’t want that either). I guess I was a little confused by the manual I downloaded from http://www.pauldesign.ru/. I think that it isn’t the same thing that you are reading.

I just pulled the ICU out of my car and examined it. Unfortunately, the circuit board looked good. I was hoping that it would be charred rubble so I could just replace the ICU and be done with it. Now I think that it might be something that is connected to the ICU and I am going to need that factory service manual. I am going to place a bid on ebay right now.

And just for everyone’s information, I called a local junk yard and the guy said it would be about $75 for a new ICU. However it sounded negotiable.

Thanks for all the help so far. I will probably post some more questions after I get the factory service manual.

[AZmike]

Don't go to the yards that have a parts counter. Go to the ones that you go and pull the part yourself. They won't know (or really care) what it is and probably not ask for more than $10-15.

[AccordEpicenter]

yea for real... I might have one around here i could sell for way way way less than the junk guy...

[GooperMC]

AccordEpicenter, AZmike: I appreciate the advice and the offer however I don't think my ICU is the problem. It looks more like something that is connected to my ICU is causing it.

Moodybluesr: Are you getting this information from the Factory Service Manual or the Electrical Troubleshooting manual? I just want to be sure I am getting the right manual before I buy it and then wait for shipping.

Thanks

[Oldblueaccord]

Heh

They prolly got ICU and ECU mixed up when you talked to them. $75 for an ECU sounds about right generally speaking ......for an ICU for our cars WOW!


Haven't tested my car yet but I got and amp clamp ordered OTW be good little project to try it on.

I had a 5 amp draw on my old Dodge the battery stay up 48 hours I dont think 250ma is really big. Just for note it ended up being the starter drawing the battery down.

Good diagnostic work GooperMC your more of a trouble shooter then you think.


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[Moodybluesr]

I got my info from the FSM. Oldblueaccord is right though; don't call a junkyard and ask for the ICU... that sounds expensive. Ask for the little black box that controls the seatbelt and key alarms under the center console... the price will probably come down dramatically.

[GooperMC]

Thanks for the advice guys. That is a very good idea. However at this point do you think that it is my ICU? I suspect that it is something connected to my ICU.

Moodybluesr. Unfortunately there is only 1 FSM up on ebay. I have placed a bid and will check it frequently, keep your fingers crossed.

[Oldblueaccord]

Thanks for the advice guys. That is a very good idea. However at this point do you think that it is my ICU? I suspect that it is something connected to my ICU.

Moodybluesr. Unfortunately there is only 1 FSM up on ebay. I have placed a bid and will check it frequently, keep your fingers crossed.

I think your on the right track its what hooked to it is the draw. I use the Chiltons book I think its #8255. Its the big think one green cover has all the stuff the FSM has plus better pics english is a little better too. Should be able to get them anywhere. Dont forget library just copy what you need. i do it for all the Chevy and ford junk I work on all the time.


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[Oldblueaccord]

Well just to type this for the fourth time 250 mA aint that much . I just amp clamped mine and I got .5 amp (500mA ) draw. Just some real data to back up the "talk."

SO i guess were in the same boat. I checked my old truck and it read about .17 its really old NO electronic crap.

Mine battery holds about 2 weeks decent weather.


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[AccordEpicenter]

if you were really pulling 500mA with the car off (dome light off etc... EVERYTHING off) if you left it for a day itd probably be dead, and 250mA would get you pretty much the same results... maybe a little longer to drain tho. Seriously guys, all working right, these cars shouldnt draw more than about 10-15ma with EVERYTHING OFF.