How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask sprinkles08 Your Own Question
sprinkles08
sprinkles08, ASE Certified Technician
Category: Australia Car
Satisfied Customers: 21601
Experience:  ASE Master and Advanced level certified. Factory trained with 15 years dealership experience
9825021
Type Your Australia Car Question Here...
sprinkles08 is online now
A new question is answered every 9 seconds

Toyota Rav4: ,My 2001 Rav4 (RHD) keeps blowing the 10a

Customer Question

Hello,
My 2001 Rav4 (RHD) keeps blowing the 10a hazard fuse when using blinkers
Submitted: 1 year ago.
Category: Australia Car
Expert:  sprinkles08 replied 1 year ago.
Hello and welcome to Justanswer!
The fuse is blowing because of high current draw on the circuit. The problem is almost surely a short to ground somewhere in the wiring.
If it only blows when turning one direction that narrows down which side of the vehicle the short is on.
A short to ground in the wiring could be anywhere between the fuse and the lights, either front or rear. A short can happen anywhere and for many reasons. It could be a wire that has rubbed through, it could be as simple as a sharp spot weld that has finally cut through insulation, or wiring could be pinched. If the problem happened as a result of an accident for instance then it makes a pinched wire likely.
The most common place to find a short t ground in lighting circuits would be trailer wiring. Trailer wiring can rub through, melt on exhaust, etc, or sometimes a short will develop right in a connector or 4 way adapter plug. If you have trailer wiring that's the first place I would recommend inspecting.
Customer: replied 1 year ago.
No trailer or any after market accessories. With the fuse pulled, I can only measure 0.06 volts on one side of where the fuse plugs in. Seems to be fairly consistent whether or not the circuit is powered.
Expert:  sprinkles08 replied 1 year ago.
You would need to measure resistance to ground on the output side of the fuse. If the fuse is blowing then you should find very low resistance.
Customer: replied 1 year ago.
What reading should I be expecting? Remember, the fuse doesn't blow instantly. I can usually drive for about 100 metres before it blows. When standing still, the fuse won't blow & i can leave the blinkers or hazards on for a few minutes with no problems. Shouldn't the input of the fuse be 12v & not 0.06?
Expert:  sprinkles08 replied 1 year ago.
With all bulbs disconnected you should see infinite resistance from the output side of the fuse to ground.
With the turn signals on and key on there would be battery voltage at the fuse. There has to be voltage at the fuse if the turn signals work until the fuse blows.
Customer: replied 1 year ago.
Thanks,
I'll measure again in the morning (it's 2.41 am here).
Expert:  sprinkles08 replied 1 year ago.
You're welcome!
Customer: replied 1 year ago.
OK. I managed to measure 13v on the input side & 3.4v on the output side when the blinkers were turned on. My mistake was not connecting the ground probe to a proper "ground". I was initially just touching a metal part of the fender.I also managed to measure infinite resistance on the output side of the circuit. What's next? Can I disconnect a plug to remove the two rear blinker lamps to eliminate that part of the circuit or will all blinkers just not work at all.
Expert:  sprinkles08 replied 1 year ago.
The issue is that the fuse only blows while moving so the short is intermittent. You most likely have a wire shorting to ground somewhere in the harness as it bounces around. You can set the meter up to monitor resistance and turn the alarm on if you have one, then you can wiggle test wiring and see if you can get the short to appear.
Customer: replied 1 year ago.
Don't have an alarm. When shorted, how will the resistance reading change? I have most of the lower dash removed, there's a bunch of junction boxes. Online resources seem to be geared towards LHD. Which side of the car does most of the blinker wiring run through on a RHD?
Expert:  sprinkles08 replied 1 year ago.
You should see infinite resistance at all times, any resistance indicates continuity to ground.
I'm away from my Toyota service information until this evening but I'm not sure I have reference for an export right hand drive; I would expect the wiring to run down the opposite side from a left hand drive vehicle.