fj62 dome light circuit parasitic draw (1 Viewer)

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I have it on pdf ..let me know which section and page and i'll give it a shot
What is the Toyota publication no. (should be on the 2nd or 3rd page of the FSM) for that FSM? If you post up that number, I check to see if I have it already in .pdf...if not, maybe you could post up an image of the circuits behind the Dome fuse...Thx.
 
What is the Toyota publication no. (should be on the 2nd or 3rd page of the FSM) for that FSM? If you post up that number, I check to see if I have it already in .pdf...if not, maybe you could post up an image of the circuits behind the Dome fuse...Thx.

pub # RM080U and #36362E...I took a look but really have no idea what you are looking for...:doh:

My sig has a link to a dropbox file for the fsm's, if that helps
 
pub # RM080U and #36362E...I took a look but really have no idea what you are looking for...:doh:

My sig has a link to a dropbox file for the fsm's, if that helps
Oh, I didn't notice the links to the fsms in your sigline...I'll take a look.

The #36362E is the one I've been looking at...
 
Well, easy enough to rule that sucker out of the Parasitic Drain Equation. ... Unplug the box. . ( behind the passenger's floor kick panel. It's labeled "cooling fan relay" or something like that.


FSM says relay is on driver's side for FJ62.
 
What is the Toyota publication no. (should be on the 2nd or 3rd page of the FSM) for that FSM? If you post up that number, I check to see if I have it already in .pdf...if not, maybe you could post up an image of the circuits behind the Dome fuse...Thx.


Photo from my FSM
cooling fan0001.JPG
 
Yes the little relay is on the drivers side up under the dash. The other"RELAY" which isn't really a relay in the normal sense of what we would call a relay (shown as the big rectangle on the drawing) is behind the PS kick panel.
 
I tested the cooling fan motor relay, which is located right under a box that says cooling fan on the driver's side kick panel (On my 62). It failed the second continuity test, which is checking for continuity between terminals 2 and 4 while 12 volts are applied across 1 and 3. So, this could be my problem, yes? Or would this only affect the operation of the fan? I've removed it and will put my dome fuse back in.
 
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I tested the cooling fan motor relay, which is located right under a box that says cooling fan on the driver's side kick panel (On my 62). It failed the second continuity test, which is checking for continuity between terminals 2 and 4 while 12 volts are applied across 1 and 3. So, this could be my problem, yes? Or would this only affect the operation of the fan? I've removed it and will put my dome fuse back in.
I've labeled the Cooling Fan Motor Relay below.

When you tested for continuity between 1 and 3, you are testing the inductor side of the relay. It did (and it should) show continuity because it is simply a wound wire.

When you tested for continuity between 2 and 4, (with no voltage applied between 1 and 3), you are testing the switch side of the relay with the switch OPEN. It did not (and should not have) show continuity, because the switch is OPEN (no path for current to flow).

When you tested for continuity between 2 and 4 with a voltage applied between 1 and 3, you are testing the switch side of the relay with the switch CLOSED. It did not (BUT SHOULD HAVE) shown continuity, because the switch did not close...it remained open.
With a voltage applied between 1 and 3, the current flowing between 1 and 3 generates an electromagentic field when it flows through the coiled wire windings. That field acts on the switch and pulls it closed.
The switch isn't closing.

FJ62 Cooling Fan Motor Relay_labled_1988 FJ62 FSM.jpg
 
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So, this could be my problem, yes?

It might be the problem...if current is leaking through the Cooling Fan Motor Relay, through the Fan Motor and on to ground.

But another path might be through the inductor side of the Cooling Fan Motor Relay, through the Cooling Fan Relay and on to ground.

The path to ground through the Cooling Fan Relay appears to controlled by both the Manifold Temperature Sensor at point 1 and some electrical component (presumably some capacitor type device that behaves as a timer) operated by the Ignition Relay at point 2.

The Manifold Temperature Sensor...when it is hot enough...will ground and close a path to ground point 1 in the Cooling Fan Relay.

Another condition appears to be at point 2, where every time the The switch side of the Ignition Relay appears to ground at through the Cooling Fan Relay at point 2...and behaves as a 'timer' that opens after a certain amount of time since the ignition was last on.

Point 3 is the ground for the Cooling Fan Relay.

So, you might be faced with a situation where the Fan Motor is not kicking on because the Cooling Fan Motor Relay is bad, but there could also be a short to ground inside the Cooling Fan Relay.
 
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Cooling fan relay doesn't appear to be labeled. It looks like there are four plug ins on that passenger kick panel side: Biggest one says O/U, a couple are easily read and not it, and one more that I couldn't read upside down.
 
I tested the cooling fan motor relay, which is located right under a box that says cooling fan on the driver's side kick panel (On my 62). It failed the second continuity test, which is checking for continuity between terminals 2 and 4 while 12 volts are applied across 1 and 3. So, this could be my problem, yes? Or would this only affect the operation of the fan? I've removed it and will put my dome fuse back in.
GASHOG, I just thought of something...

... on the Cooling Fan Motor Relay, check for continuity (with no voltage applied) between:
1 and 2
1 and 4
2 and 3
3 and 4

If any one of those combinations has continuity between them (they should not), then there is a short within the relay to ground (in addition to the switch side of the relay not functioning properly).
 
...If any one of those combinations has continuity between them (they should not), then there is a short within the relay to ground (in addition to the switch side of the relay not functioning properly).

All of the combinations tested out OK.
 
All of the combinations tested out OK.
Hmm...then I would suspect the Cooling Fan Relay as the source for the short. Either way, you will probably have to replace the Cooling Fan Motor Relay (because it isn't switching properly), but if your parasitic draw goes away with both relays disconnected, then I would assume the Cooling Fan Relay to be at fault.

You might be able to remove the cover to the Cooling Fan Relay and see if any of the solder lines have run together...creating a short. I'm not sure how the circuitry on the Cooling Fan Relay is supposed to work (having never reverse engineered one) and I haven't see any troubleshooting procedures in either of the FSMs, so depending on the results of your parasitic draw test, it might come down to replace and retest type of trouble shooting...
 
I did pull both out, and all seems to be well now. I'm thinking about wiring a switch to the cooling fan to turn in on/off manually in the cab rather than deal with the relays. Anyone see a problem with that?
 
Update on this. Pretty sure I've finally found the actual culprit now. It's the aftermarket stereo! Definitely pulling some mA's whether key on or off-power button on or off.

Since the power connection responsible is readily accessed, I'm thinking of just putting it on a switch. It's an old radio/CD player without bluetooth, etc. and wouldn't be able to save radio stations but what the heck. Don't really use it that much anyway. Dome light is very nice to have in the dark winter though.
 
Carb cooling fan relay. BTDT.
I know this is a really old thread but I have to jump in to ask! I've read through this thread but I'm concerned about a couple things: (1) carb cooling fan relay - I have a fuel injected FJ62...do I even constitute having this relay since I'm not carbureted? (2) I've found a parasitic draw on the dome light fuse port and the cig fuse port (which for some reason also powers my radio)...so I pulled these fuses several months ago. BUT I want to have a radio in my vehicle, I want to have dome lights AND I don't want my vehicle to not start every few days because of a dead battery. Before I removed these fuses, I'd have to jump my baby every Monday morning before work. Now she starts every time, without hesitation, but I don't have a working radio or working dome lights.

Cooling Fan Relay, part # 85927-60040 (this part indicates it's for the 1981 2F engine..."Nancy" was born in Sept 1989 and sold as a 1990).
 
Try this as a test. Next time you park let the fan run until it stops. Then pull the dome fuse just overnight. See if the battery is happier.
then, if that works, next time, if you can time it, just unplug, replug the fuse.

my issue is a sticky relay connection Or somthing like that. It was a nightmare to find. Here’s my scenario.
- had about .15v parasitic draw.
- pull dome fuse it disappeared.
- reinsert All good, no draw
- turn on ignition, it’s back!
- lots of hours later I determined by pulling that dome fuse (same circuit as fan), it would kill the fans parasitic draw until I started the car again or turned key to ignition.
- new routine until I fix relay for real is to remove and reinsert that fuse. That does it.

It’s like the relay sticks a little bit until you removed all electrical to it.
 
Try this as a test. Next time you park let the fan run until it stops. Then pull the dome fuse just overnight. See if the battery is happier.
then, if that works, next time, if you can time it, just unplug, replug the fuse.

my issue is a sticky relay connection Or somthing like that. It was a nightmare to find. Here’s my scenario.
- had about .15v parasitic draw.
- pull dome fuse it disappeared.
- reinsert All good, no draw
- turn on ignition, it’s back!
- lots of hours later I determined by pulling that dome fuse (same circuit as fan), it would kill the fans parasitic draw until I started the car again or turned key to ignition.
- new routine until I fix relay for real is to remove and reinsert that fuse. That does it.

It’s like the relay sticks a little bit until you removed all electrical to it.
Yeah, that's very similar to what's happening with mine. The aftermarket radio is also pulling a ton of power and there's no way to turn that radio off. So I've had the cig fuse and the dome fuse removed for like 6 months. I finally put an LED into my dome light fixture last night and then replaced the 7.5 fuse. The light doesn't turn on. So I got to thinking that maybe something else that's connected through that same wiring is broken or malfunctioning. Then, after reading this forum, I was wondering if it was that cooling fan relay thing...but I can't seem to locate it under the hood. Tonight, I will put my 15 cig/radio fuse and my 7.5 dome fuse back in to see what happens.
 

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