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My 2001 Toyota Rav4 Check engine light came on and at the same time I lost use of passenger power windows (drivers window still works). Heater fan also quit working and speedometer quit working. Drove it to the Toyota dealer for diagnosis... my battery ran down overnight so they replaced battery, cables and pads to get it going. Next they replaced a fuse which seemed to fixed everything. They took it out for a test drive and the fuse blew again. I was told that they want to continue to charge me to diagnose a possible electrical short and I'm already in it $460.00. Any ideas? Computer code was P0500 which is "vehicle speed Sens Malfunction".
 

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I just recently ran into this problem with my 03 RAV4. What a pain it was figuring out what the heck was going on here. This 10A Gauge fuse controls the power for half the car, but I just got a box of fuses and started disconnecting things one at a time and driving it. The fuse would only pop under load while driving at least that's what I thought. While playing with the cooling fans and the relays I got the fuse to blow while sitting in my garage. I ended up disconnecting the coolant temp sensor that's right by the thermostat housing and took it for a test drive. (If you do this keep the defrost or AC on so the cooling fans run and you don't overheat, because it disables the temp gauge as well) Well no fuses blew and I am suspecting that coolant temperature sensor is the culprit.

This thing drove me crazy for two days mainly because it triggered a P0500 code. I kinda thought that was only a side effect from the fuse blowing because that gauge fuse controls the speedometer and the odometer, as well as a slew of other things. It was not the vehicle speed sensor, to test this I just unplugged speed sensor on the back of the trans to see if the fuse blew while diving and it did.

Just an FYI dont start unplugging things unless you have an OBDII scanner or tool to clear the codes. You dont want a bunch of codes hanging out in the ECU and it will trigger an engine light when you start unplugging and driving.

Things this fuse controls:
- Speedometer and odometer
- Cooling Fans, Cooling Fan relays, Coolant temp sensor
- Power windows (except drivers side)
- Alternator/charging system
- Blower motor
- Back up lights
- Shift indicator on the the dash that lights up
- Vehicle Speed Sensor
- Also sends a power signal to the ECU
 

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I have the exact same problem Five30. Can you tell me the location of that 10A fuse? Under the hood, or behind the "storage box". Thanks for posting this. I'm getting the 0500 code and I thought it was because I just had the transmission rebuilt.
 

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For those following at home.... I think I located the fuse that five30 will eventually verify. I initially tested just the 10 amp fuses inside the car. They all checked good. Then I decided to check all the fuses under the hood and didn't find any popped. So I went back inside the car and checked ALL the fuses. I had a popped 20 amp fuse in slot 28. Ran up to the local AutoZone and bought a package of 20 amp thinking this could be it. Before I put it in and test for fan motor, I double checked what amperage it should be. 10 amp... So there has been trouble here before. I'm too burned out to run up to AZ and get a pack of 10 so this will be continued tomorrow.. I'm just curious if it could have anything to do with my transmission getting rebuilt this week. I also found the negative cable on the battery loose...
R&R
 

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For those following at home.... I think I located the fuse that five30 will eventually verify. I initially tested just the 10 amp fuses inside the car. They all checked good. Then I decided to check all the fuses under the hood and didn't find any popped. So I went back inside the car and checked ALL the fuses. I had a popped 20 amp fuse in slot 28. Ran up to the local AutoZone and bought a package of 20 amp thinking this could be it. Before I put it in and test for fan motor, I double checked what amperage it should be. 10 amp... So there has been trouble here before. I'm too burned out to run up to AZ and get a pack of 10 so this will be continued tomorrow.. I'm just curious if it could have anything to do with my transmission getting rebuilt this week. I also found the negative cable on the battery loose...
R&R
I sent ya a PM. I'm not sure which slot it is but the fuse is labeled "gauge" in the interior fuse box lower left of steering column.When it blows you loose the speedometer, cooling fans, alternator, blower motor.

Also the coolant temp sensor isn't behind the t-stat housing as I mentioned, its behind the upper radiator hose inlet pipe just above the starter.
 

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Thanks much for the response five30. I started replying in a pm and changed to here for more input for both of us and maybe the next guy... I talked to a friend of mine tonight about that sensor shorting out, and he thought if the part inside the sensor broke down and touched the side it would be a short. He told me since yours was fixed by it I should just change it since its a fairly cheap part. I found the fuse you were talking about when I started pulling them one at a time instead of just the 10's. I didn't see it initially because the previous owner had stuck a 20 in there.
Can you explain to me a little more about how the fuse popped when you were messing with the relays, (my friend has a relay tester he's letting me borrow tomorrow) and how you determined it was the temp sensor? (last thing to check?) I also thought about disconnecting things one at a time, but thought back up lights, and drive indicator lights would be way at the bottom of possible problems. And since there so many items on that fuse, is my terminology correct that a fuse 28 is only supplying trigger voltage to those circuits, like cooling fan motor, or blower motor, or power windows? So if I disconnect a relay and the fuse doesn't pop, I can isolate which circuit has the problem?
Thanks again for the help. I'm really anxious to get my truck back and my daughter driving her "new" car.
R&R
 

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Just unplug the coolant sensor and drive it, you won't have overdrive and the CE light will come on but you will know if that's whats causing it or not.

So while I was messing with the relays a buddy of mine was giving it gas trying to get the fans to cycle and it popped sitting in the garage. So we tried it again only messing with acceleration and bringing the rpm's up while the temp gauge was at normal operating temp (about half way) and it popped the fuse.
To elaborate a bit more on what I figured out, I figured out that the fuse was popping around 2500-3000 rpms, I started going through the list of things on that circuit that are effected by the rpm's. Coolant and the fans, I got the fans to come on by cycling the A/C and the defrost but they wouldn't cycle under normal conditions, what controls the fans? the Coolant temp Sensor, what moves with the RPM's across the coolant temp sensor? coolant. That's my deduction of what was causing it.
 

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Took the Rav out tonight thinking I had disconnected the temp. sensor. After driving around for a couple minutes I noticed the temp guage moving towards the center. Wrong one. This gauge only has a single wire to it. Neighbor told me maybe a fluid level sensor? When I opened the hood the fans came one too. After a few minutes I decided I'm taking it to work tomorrow and see what happens. Right now everything is working as it should. I will try and see if I can do something to make the fuse pop. I don't see any wires running through the fire wall that could be frayed. It actually looks like its rubber lined...
Thanks for the explanation Five30.
All systems plugged back in.
Test results to follow.
 

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Its a 2 wire sensor just above the starter, Its on the head/engine. Follow the upper radiator hose from the radiator to the engine and its just behind the neck that sticks out off the engine for the radiator hose. My fuse was popping within 5- 10 mins of driving it. You'll know if you unplugged it because you won't have a working temp gauge and you won't have overdrive.
 

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Thanks Five30, I did locate the fuse. I've been driving the car around for the last 2 days, with 50 miles or more, including a 25 minute stint on the interstate at 65 and 2800 rpm and the fuse has not blown. The worst thing is not having the heater blower motor.
So if fuse 28 is popped does this mean I have no engine cooling fans or temp indicator on the dash so I could be overheating and not even realizing it? I hope I'm wrong. I drove home last weekend for about 20 minutes with the blown fuse and didn't overheat unless I was on the verge of overheating and didn't know it...
 

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Thanks Five30, I did locate the fuse. I've been driving the car around for the last 2 days, with 50 miles or more, including a 25 minute stint on the interstate at 65 and 2800 rpm and the fuse has not blown. The worst thing is not having the heater blower motor.
So if fuse 28 is popped does this mean I have no engine cooling fans or temp indicator on the dash so I could be overheating and not even realizing it? I hope I'm wrong. I drove home last weekend for about 20 minutes with the blown fuse and didn't overheat unless I was on the verge of overheating and didn't know it...
Not sure I am following you here. You said the fuse did not blow but you said your blower motor isn't working. Did you locate the correct coolant temp sensor and unplug it? You shouldn't be driving around for days with stuff unplugged, only unplug stuff for testing purposes (i.e. short trips with the car at operating temperature.) I'm a little confused with this last post you made as to what you did/didn't do or if the fuse is blown or not. If that fuse blows you will immediately know because your speedometer will quit working, along with all the other stuff I listed in the previous post.

If you have located the Coolant Temp Sensor (2 wire plug) and unplugged it and your fuse is no longer blowing well there's your problem. They are about $20-$30 and take about 20 minutes to change.
 

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Sorry for the confusion. I replaced the fuse when it blew on me last week for the second time. The first time was when I got it back from the transmission place. That's when I read your reply to Daellis. Everything is now working as it should. I've driven the car for close to 100 miles and the fuse has not popped again. I'm going to drive it to work all week which is 25 miles round trip per day. My reference to the blower motor was I wouldn't care as much about the blown fuse if I had heat in the car...������.
I think I can safely say I don't think my problem is the temp. sensor. Maybe a bare wire somewhere waiting to touch again...
side note: has anyone ever used the power probe ECT 2000 for finding shorted wires?
As far as the 10 amp fuse you found popped with everything associated with it, I'm concerned if this fuse pops again and I cant get a new fuse to stay in without popping again, am I chancing overheating!!!
 

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Yea if you have been driving around with out it blowing the fuse again I doubt its the sensor. As far as overheating, maybe if it happens in the summer, I doubt that engine would overheat in the winter. One thing is, if it blows you loose your speedometer and the CE light comes on, so you should be aware that the fans won't be working and can just limp her home. You may have remedied the issue with something you did already. I wouldn't go digging through circuits if you don't have to. Good Luck! If you have any other questions just post it here I get the email alerts and will do what I can to help.
 

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Appreciate the responses Five30. I've driven it all week and haven't had the fuse blow again. Over 200 miles. My new problem is with the low idle, which has a 6 page post already and no definitive answer there either....way too much electronics in these cars today�� IMO...
 

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Well as fate would have it, I brought the Rav to my daughter on Thanksgiving after 2 weeks of no fuse popping. It was nice to have my truck again. On her way to work today the fuse popped! I did notice that she has a temperature gauge so now I have a little peace in knowing without fans being operational, at least Toyota will let's us know if we are about to over heat!
I'm planning on going to the junk yard tomorrow and see if I can do some signal tracing between the #28 fuse and the main block under the hood. I want to find which wires go where. I'm bringing my Chiltons manual too.
Something I would like to do is wire my own switch so I can at least turn on a radiator fan in the event of the fuse popping. This should be realitively easy right? It just has to be able to also run normally of the fuse doesn't pop. Anyone have any thoughts?
Thanks and Happy Thanksgiving +1
 

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My junkyard trip was almost... a waste of time. The 2003 that was in there someone tore the interior dash apart and I couldn't get the hood open. 1/2hr. Later I'm in. I learned that I'm going to need a pretty good wiring harness diagram to do any wire tracing.... Since the fuse is so intermittent for me, I'm going to teach my daughter how to change the fuse when it pops and wait until it's either an open or its welded itself to ground? I've shaken, pulled, wiggled, swore at, driven over some very bumpy roads all since I got the car back yesterday and the fuse has not popped again. About 30 miles and 1 hour of driving on interstate and urban. Not sure what else I can do. Will report back if I discover anything for the next guy who might have a similar problem.
Five30, have you had any more problems since you replaced the temp sensor?
Thanks
R&R
 

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4 weeks later.... I decided to take the car to the same guy who changed my transmission since I got the car back with the fuse popped. I told him I didn't blame him, the car has a history...at least that's what I have been finding out. The fuse was starting to pop within minutes of starting as apposed to weeks. He told me he could put a meter on the radiator fan (one of my suspicions) and test it's draw, and I felt like he had a pretty good handle on things so I left it for him to start on it last Monday. By noon he had found the suspected problem. The "ballast for the heater motor" was being dripped on by A/C condensation over the summer I guess cause it's winter now, and had corroded the connections and had one wire he had to replace. He told me he was 100% sure it was the problem. $195.00 later I'm trilled. The resistor was $85!
I don't know how else to have dealt with this problem since it was so intermittent at first. I'm driving it to work all week, and if there are no problems my daughter will drive it home after getting together for Christmas.
I hope this helps someone to at least know one place to start looking and that my story is over... Wonder what happened to Five30? Lol
Merry Christmas all!
 

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Turns out this happened to me again and I came back to this thread. This time it was my blower motor resistor as well. Thanks riseandrun. Almost 2 years to the day lol.
 

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Well Merry Christmas and Happy New Years! This is why I like to always finish my posts with what the solution to the problem was! I friend of mine at work had a 2002 Rav 4 manual, and she put almost 350K on her car with never a bit of engine work, and it was still running when she got rid of it! FWIW lol.
 

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Merry Christmas and Happy New year to you too Riseandrun! Yes this vehicle has been great I ended up giving it to my daughter about a year and a half ago for her first vehicle and it's been going strong until this little hiccup again. We are right at 200k miles (196k to be exact).

I have this clunking in the front end I'm going to have to research now. It's a 2 wheel drive and I've replaced everything except the inner tie rods. And I think that's the culprit. I've put struts (whole unit with mounts), control arms, ball joints, outer tie rods and the clunk is still there. Other that that it's great!

Is yours still going?
 
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