Cooling fan resistance?

[hondaaccorddrew]

I have been tracing a ground that starts in my fuse box, and that the wire grounding out was blue w/black stripe. In another post, I discussed finding it and that it leads to the engine cooling fans. Here's the issue. On the continuity test, the meter beeps steady when checking the disconnected terminals on both fans. Fan one has .002 ohms grounding to postive, and fan 2 has .004. Both fans work, but I do not wanna blow another alternator cause it's generating on a grounded connection. When I disconnect them, the fault to ground disappears from the wire and the fuse box. What is the resistance on the fan motor supposed to be? Is this normal or are they trash? They are $150 each... so... any help is appreciated!

[88Accord-DX]

There are no kind of specs for resistance for the cooling fan... If ur worried about a circuit or ground, put a load on that circuit with some leads to a headlight bulb.. 12 volt sorce on the other end..

[lostforawhile]

I have been tracing a ground that starts in my fuse box, and that the wire grounding out was blue w/black stripe. In another post, I discussed finding it and that it leads to the engine cooling fans. Here's the issue. On the continuity test, the meter beeps steady when checking the disconnected terminals on both fans. Fan one has .002 ohms grounding to postive, and fan 2 has .004. Both fans work, but I do not wanna blow another alternator cause it's generating on a grounded connection. When I disconnect them, the fault to ground disappears from the wire and the fuse box. What is the resistance on the fan motor supposed to be? Is this normal or are they trash? They are $150 each... so... any help is appreciated!

you are just reading a phantom ground through the fan motor is all. if you hook the fan to power and it spins,it's fine. if it was shorted out that badly,it wouldn't work at all.

[lostforawhile]

no power from the under dash fuse panel goes directly to the fans, there is a black/yellow wire from fuse 12 in that fuse box, but it's to power the fan relay,not directly power the fans. The fan power is blue/black and black, but it goes directly to the fan relay in the underhood fuse box. power to that relay comes directly from fuse 9,which is 30 amps and under the hood, if you had a fan short, it would blow fuse 9 under the hood. The AC circuit is very simple in the way it controls the fans, the fan relay is switched on by the coolant switch grounding. The AC circuit simply grounds the same circuit. The radiator fan and the AC condenser fan are both wired together, they should both run. If this was an LXI it would get much more complicated, but yours is an lx,

[hondaaccorddrew]

no power from the under dash fuse panel goes directly to the fans, there is a black/yellow wire from fuse 12 in that fuse box, but it's to power the fan relay,not directly power the fans. The fan power is blue/black and black, but it goes directly to the fan relay in the underhood fuse box. power to that relay comes directly from fuse 9,which is 30 amps and under the hood, if you had a fan short, it would blow fuse 9 under the hood. The AC circuit is very simple in the way it controls the fans, the fan relay is switched on by the coolant switch grounding. The AC circuit simply grounds the same circuit. The radiator fan and the AC condenser fan are both wired together, they should both run. If this was an LXI it would get much more complicated, but yours is an lx,

Yeah they both run when the AC is on, and when the set temperature for the thermoswitch is achieved. I have a problem somewhere though cause it was grounding completely with no resistance on this blue/black positive wire. Also, under full electrical load (headlights, AC, fans, window defroster) everything is dim and under 12.3 volts with the engine running. Turn everything off, and it jumps up to normal charging voltage. Either all my previous alternators cannot supply the current under load at idle, or something is wrong.

[Oldblueaccord]

Might be a pretty big amp draw all that running esp since its all old stuff. The rear defroster esp can pull a lot. A lazy fan motor can also. AC clutch can too if its gap is out of spec.


wp

[lostforawhile]

Yeah they both run when the AC is on, and when the set temperature for the thermoswitch is achieved. I have a problem somewhere though cause it was grounding completely with no resistance on this blue/black positive wire. Also, under full electrical load (headlights, AC, fans, window defroster) everything is dim and under 12.3 volts with the engine running. Turn everything off, and it jumps up to normal charging voltage. Either all my previous alternators cannot supply the current under load at idle, or something is wrong.

check the ground strap between the engine and the body,make sure the terminals are clean especially . I don't think you have a short a digital meter can fool you with low resistance,also several items are connected in parallel to the circuit you are measuring,making it appear to have no resistance, it's not really shorted, a short bad enough to drain the alternator would be causing smoke and flames by now

[Vanilla Sky]

Sounds like you're reading some phantom voltage there.

http://en.wikipedia.org/wiki/Stray_voltage

[hondaaccorddrew]

Guys, I just blew my 3rd alternator in the past 6 months. This one only lasted a month, the last one lasted 30 mins but I had a shorted choke heater. Something is up... and I am not reading any grounds except for the fans. Suggestions?

[Vanilla Sky]

Have you replaced the battery, or at least had it tested? A shorted battery will do that to an alternator.

[hondaaccorddrew]

Have you replaced the battery, or at least had it tested? A shorted battery will do that to an alternator.

Yeah, the battery is new. I even decided to do deep cycle and make sure it was charged, just so when the alternator died out again, I could still do my driving and then re-charge when I got home.

[hondaaccorddrew]

Well, I guess this goes back onto the subject of grounding out. I started tracing that thick blue/black stripe wire again. Disconnected the two fans, the temp switch, and it also goes underneath the passenger compartment to the blower and the resistor for the fan speeds. After disconnecting all of that, the fan would only run on high. The short would go away if I turned the dial to anything but the "HI" function. But it was still present. It was grounding out with no resistance. I followed it to a large blue plug under the steering wheel. When I disconnected it still stayed grounded, but the cooling fans and blower no longer had power. Then, I turned off the ignition. What does this mean? I doubt this wire is supposed to be switched to ground when it's the hot to everything else it's attached to. The ground is only gone if the ignition is off and the large plug is removed. Where else does this wire go? I hope I do not sound obcessed. But since I have trashed several hundred dollars in alternators, this is my only lead. Thanks to all.

[ecogabriel]

Yeah, the battery is new. I even decided to do deep cycle and make sure it was charged, just so when the alternator died out again, I could still do my driving and then re-charge when I got home.

Have you replaced the battery's GROUND wire? I do not know if a a lost ground may kill an alternator, but I know my car started doing strange things -lights going very low when pressing the brake light at night.

The wire is very thin, and just decided I would replace it. No more problems.

[hondaaccorddrew]

Have you replaced the battery's GROUND wire? I do not know if a a lost ground may kill an alternator, but I know my car started doing strange things -lights going very low when pressing the brake light at night.

The wire is very thin, and just decided I would replace it. No more problems.

Yeah, the lights go dim at night. It is quite a small battery. It doesn't look like it could cover more than 60 amps now that I think about it, which is the alternator's current rating. With the lights on at night, I step on the brakes or I am at idle everything goes dim. More RMP's fixes this, everything is back up to brightness. Worse when the defogger is on. After I fix this problem with grounding out and toasting alternators, I will try replacing this to hope the dimming issue goes away.

[lostforawhile]

Yeah, the lights go dim at night. It is quite a small battery. It doesn't look like it could cover more than 60 amps now that I think about it, which is the alternator's current rating. With the lights on at night, I step on the brakes or I am at idle everything goes dim. More RMP's fixes this, everything is back up to brightness. Worse when the defogger is on. After I fix this problem with grounding out and toasting alternators, I will try replacing this to hope the dimming issue goes away.

all the battery does is start the car and provide power if the alternator quits,the entire car runs off of the alternator, it's the most common misconception in automotive wiring, everyone thinks a bigger battery will fix all kinds of stuff, when the power to run everything comes from the alternator. You don't have a short,trust me, I've been working on car electrical stuff since I was a little kid, you have an issue with a ground, a bad connection, or the alternator isn't producing the rated output it's supposed to. there should be a strap from the transmission to the body, as well as some other grounds, undo those and clean the mounting surfaces and reinstall them. the ground strap from the transmission to the body isn't very good, I would buy a premade battery cable with an eyelet on each end, and replace that. check your battery terminals, if they are bad, the alternator will use a lot of it's output trying to charge a badly drained battery, this will also toast your alternator, it's not made to do that, it's supposed to replace the charge from starting the car, and that's it. The lower the battery voltage, the more current is going into it trying to charge it, a battery close to 12 volts,isn't using much charge current,vs a battery much lower. Take the car to an auto parts store, etc, who can measure charging current, have them check the actual output of the alternator while it's heavily loaded I'll bet the current is way down.

[hondaaccorddrew]

all the battery does is start the car and provide power if the alternator quits,the entire car runs off of the alternator, it's the most common misconception in automotive wiring, everyone thinks a bigger battery will fix all kinds of stuff, when the power to run everything comes from the alternator. You don't have a short,trust me, I've been working on car electrical stuff since I was a little kid, you have an issue with a ground, a bad connection, or the alternator isn't producing the rated output it's supposed to. there should be a strap from the transmission to the body, as well as some other grounds, undo those and clean the mounting surfaces and reinstall them. the ground strap from the transmission to the body isn't very good, I would buy a premade battery cable with an eyelet on each end, and replace that. check your battery terminals, if they are bad, the alternator will use a lot of it's output trying to charge a badly drained battery, this will also toast your alternator, it's not made to do that, it's supposed to replace the charge from starting the car, and that's it. The lower the battery voltage, the more current is going into it trying to charge it, a battery close to 12 volts,isn't using much charge current,vs a battery much lower. Take the car to an auto parts store, etc, who can measure charging current, have them check the actual output of the alternator while it's heavily loaded I'll bet the current is way down.

Sorry, I meant wire not battery in that first sentence where I said "it's quite a small battery." My bad. Anyhow, I guess I will replace the alternator again and try larger grounds since they are so small, and try again. When I got my battery, it showed 13.1 volts. On the current loss thing, you're right. At idle, with all of my accessories on and a *working* alternator, I have barely produced above 12.4, not including it in gear with the brake lights on also. If you're positive I do not have a short on this wire or anywhere else in my car, I will leave it be.

[lostforawhile]

Sorry, I meant wire not battery in that first sentence where I said "it's quite a small battery." My bad. Anyhow, I guess I will replace the alternator again and try larger grounds since they are so small, and try again. When I got my battery, it showed 13.1 volts. On the current loss thing, you're right. At idle, with all of my accessories on and a *working* alternator, I have barely produced above 12.4, not including it in gear with the brake lights on also. If you're positive I do not have a short on this wire or anywhere else in my car, I will leave it be.

before you go replacing your alternator have it's output current checked with it heavily loaded. if you have a bad ground it won't be able to produce maximum output either, check the alternator terminal at the fuse box, check the terminal at the back of the alternator, your alternator might be fine, but other issues are causing it to not operate properly. You said voltage goes up above idle? I've had that issue with alternators before too, they are supposed to be on at idle but some don't like to work at that low of an rpm

[hondaaccorddrew]

before you go replacing your alternator have it's output current checked with it heavily loaded. if you have a bad ground it won't be able to produce maximum output either, check the alternator terminal at the fuse box, check the terminal at the back of the alternator, your alternator might be fine, but other issues are causing it to not operate properly. You said voltage goes up above idle? I've had that issue with alternators before too, they are supposed to be on at idle but some don't like to work at that low of an rpm

I checked the terminal to the alternator and ground at the casing. No output sadly. When I was driving along, I was accelerating and suddenly my RMP's snapped up to about 5,000 and my stereo shut off and went into protective mode, same with my gauges and stuff since the alternator was overproducing. This lasted for about 5 seconds then everything came back on when the overvoltage quit and my battery light came on. At that point, I knew it wasn't charging. I've checked all fuses and connections. When the engine is running, it's running as if a load has been lifted, since the alternator isn't charging. I'll take it in for a load test when the shops and auto stores open tomorrow. And yes, unfortunately on the load thing. Being honest when I got the car a few years ago, it didn't have changes to loads. Then when the alternator went out, every replacement since allows for a drop when the car has full electrical load. Is there a chance that these alternators are coming with the wrong pully size?

[Oldblueaccord]

Did you every unhook your amp for the time being?


I bet your amp draw was 60 amps or more when it blew if your idle jumped up. I think your just drawing to much current at once.

I might be confusing your case but did you run a large wire from the back of the alt lug directly to the battery last time? that will jump around of bad connections etc. under the dash etc.


Keep thinking of all the scenarios that are making your amp draw high and eliminate them one by one.

EDIT: I followed your other post all on the same subject, You still have bad wires, grounds some place.

Quote:
Thank you so much for this info. I will look into it. Yeah both the fans work. But they draw the whole car down, is that normal?

End quote:

I would look again 1. at your choke heater 2. again at the large white wire to yur fuse box and again 3.at the wiring going to your fans and again 4. unplug your stereo amp for the time being.


wp

[Oldblueaccord]

all the battery does is start the car and provide power if the alternator quits,the entire car runs off of the alternator, it's the most common misconception in automotive wiring, everyone thinks a bigger battery will fix all kinds of stuff, when the power to run everything comes from the alternator. You don't have a short,trust me, I've been working on car electrical stuff since I was a little kid, you have an issue with a ground, a bad connection, or the alternator isn't producing the rated output it's supposed to. there should be a strap from the transmission to the body, as well as some other grounds, undo those and clean the mounting surfaces and reinstall them. the ground strap from the transmission to the body isn't very good, I would buy a premade battery cable with an eyelet on each end, and replace that. check your battery terminals, if they are bad, the alternator will use a lot of it's output trying to charge a badly drained battery, this will also toast your alternator, it's not made to do that, it's supposed to replace the charge from starting the car, and that's it. The lower the battery voltage, the more current is going into it trying to charge it, a battery close to 12 volts,isn't using much charge current,vs a battery much lower. Take the car to an auto parts store, etc, who can measure charging current, have them check the actual output of the alternator while it's heavily loaded I'll bet the current is way down.

quote
the alternator will use a lot of it's output trying to charge a badly drained battery, this will also toast your alternator, it's not made to do that,

end quote

everyone thinks a bigger battery will fix all kinds of stuff, when the power to run everything comes from the alternator.



you are contradicting yourself. I understand your trying to help and its appreciated.

in a high load situation its better to have a large battery(larger capacity) or possible multiple batteries. AKA a Diesel truck for instance has multiply batteries. Or if you use an electric winch on a Jeep two batteries are better than one.

wp

[hondaaccorddrew]

Did you every unhook your amp for the time being?


I bet your amp draw was 60 amps or more when it blew if your idle jumped up. I think your just drawing to much current at once.

I might be confusing your case but did you run a large wire from the back of the alt lug directly to the battery last time? that will jump around of bad connections etc. under the dash etc.


Keep thinking of all the scenarios that are making your amp draw high and eliminate them one by one.

EDIT: I followed your other post all on the same subject, You still have bad wires, grounds some place.

Quote:
Thank you so much for this info. I will look into it. Yeah both the fans work. But they draw the whole car down, is that normal?

End quote:

I would look again 1. at your choke heater 2. again at the large white wire to yur fuse box and again 3.at the wiring going to your fans and again 4. unplug your stereo amp for the time being.


wp

Oddly enough, my amp WAS off. My stereo was swtiched into standby and the signal wire has no power, thus the amp is off. This one only draws 30 amps and it is dual fused. I had my fan on high and the AC on, that's IT.

Like I said before, is reading a ground on that large gauge blue/black stripe wire normal? I would encourage anyone who could see if the same wire (under passenger side dash) is grounding out on their cars too. It's associated with the fan on high and the ground doesn't go away when I disconnect anything associated with it (motor, fans, blower resistor, temp switch). I will test to ground on the white wire, but I know my choke heater isn't shorting out. I replaced it, and I tested it again last night and it didn't read a short. I will keep my amp off the car until I fix this and pull my stereo plug. I bet unhealthy doeses of voltage is unhealthy for anything in my car.

[hondaaccorddrew]

quote
the alternator will use a lot of it's output trying to charge a badly drained battery, this will also toast your alternator, it's not made to do that,

end quote

everyone thinks a bigger battery will fix all kinds of stuff, when the power to run everything comes from the alternator.



you are contradicting yourself. I understand your trying to help and its appreciated.

in a high load situation its better to have a large battery(larger capacity) or possible multiple batteries. AKA a Diesel truck for instance has multiply batteries. Or if you use an electric winch on a Jeep two batteries are better than one.

wp

Unfortunately for this situation though, if it is cause of overload, the alternator is only 60 amps. If it takes 400 out of a deep cycle battery to start it, that's a lot it has to charge back up, not including other factors. Like having the headlights on, etc.

[Oldblueaccord]

I have been tracing a ground that starts in my fuse box, and that the wire grounding out was blue w/black stripe. In another post, I discussed finding it and that it leads to the engine cooling fans. Here's the issue. On the continuity test, the meter beeps steady when checking the disconnected terminals on both fans. Fan one has .002 ohms grounding to postive, and fan 2 has .004. Both fans work, but I do not wanna blow another alternator cause it's generating on a grounded connection. When I disconnect them, the fault to ground disappears from the wire and the fuse box. What is the resistance on the fan motor supposed to be? Is this normal or are they trash? They are $150 each... so... any help is appreciated!

I had one fan I pulled from a junkyard I think it works but I ohmed it out on the two pins 1.1 ohms. I don t think that means anything.

wp

[hondaaccorddrew]

My local junkyard got rid of all their early model Honda's. The nearest one is 100 miles from me.

[Oldblueaccord]

Unfortunately for this situation though, if it is cause of overload, the alternator is only 60 amps. If it takes 400 out of a deep cycle battery to start it, that's a lot it has to charge back up, not including other factors. Like having the headlights on, etc.

That battery rating is by the hour.

http://en.wikipedia.org/wiki/Automotive_battery


I doubt your car starter runs more than 90 amps. I'll check mine if I can con the wife into helping me.

I'm am not saying your amp draw is normal there something wrong somewhere in the system.


wp