Low beam headlights out//no voltage to fuse//2001

$15 at techinfo.toyota.com gets you a couple days access, which is enough to download as much of the manuals as you'd like to have on hand for later. The Electrical Wiring Diagram Manual is really useful for this kind of question. If it sounds like just a diagram, it's not; it's book sized, it does have the diagrams for every system, plus the physical locations and layouts of all the harnesses, relays, junction boxes, testing procedures, identification and part numbers of all connectors, etc. etc. If you download it you'll never be sorry you did.

-Chap

 

Are you checking for "current" or "voltage" at the fuse? If checking for current, you won't get any unless the lights are on and the fuse is in place. Current has to be measured in series (which means its hard to measure with a meter. Put your meter on DC V setting and check for voltage.

 

I am having the same issue, DRLs work fine but no change in low or high beam. brand new bulbs. checking voltage in relay and fuse center under the hood shows no voltage coming through.

 

By "no change" do you mean you can turn the headlights on, but nothing changes when you move the stalk between low and high beam? Or do you mean that neither low nor high beam looks any different from the DRLs?

As you can see on pages 80 and 81 of your wiring diagram manual, the way the circuit works takes a bit of wrapping your head around. The "daytime running light relay" (D3 on page 81) is the brains of the outfit, and not to be confused with the "DRL relay" (go figure), which is just one of the three simple relays controlled by the thing at D3. (One of them switches the lights on or off entirely, one selects the high or low beam filaments, and one selects whether they get full voltage for headlight use, or the pulse modulated voltage for DRL use.)

The tables on page 82 (parts location, relay blocks, junction blocks) will help you find where these things all are in the car. For example, you can see that the "3" in an oval refers to relay block 3, "1E" and "1F" in ovals are in the "engine room junction block", and they'll tell you to see pages 24 and 27 respectively for the details of those, and those detail pages will also direct you to the page showing their physical locations.

Happy hunting!

-Chap

 

Happy hunting!

-Chap[/QUOTE]


well... in terms of hunting I suppose you meant for the manual. I have been to tech info... I have called the Toyota number. no luck on the manual I need. I have spent about 21 hours on Google looking for the manual that includes the wiring diagrams I need.


I do have an update on my situation though. now I have DRLS in normal operation. 1 click forward on the stick gives me front running lights (markers) and 2 clicks forward shuts everything off.

now I'm really confused.

Mike

 

Those whom the Gods would destroy ...

Bob Wilson

 

Yikes! 21 hours of your time is worth a lot more than the $15 techinfo subscription.

Are you saying that when you signed in to techinfo, you honestly couldn't find the "Prius Electrical Wiring Diagram, 2001 model" publication number EWD414U ?

It should definitely be there, and if there's a problem and they took your fifteen dollars, you should definitely insist they fix the problem.

-Chap

 

the only manuals they have on there are scheduled maintenance, emergency response, and suppliments to each of the above mentioned. I have send them a help request on the situation, however that still leaves me searching the infinite Web for more answers on where to find the book.

I have found hard copies for sale... ranging from $75-90 US. seems a little outrageous to me. but if I can't find something better soon it will be my only option.

thanks for the help fellas

Mike

 

It sounds like you've been looking under the "Manuals" tab that shows up before you sign in. Those are the free ones. Did I mention there's a $15 subscription for access to the service lit? Looking over other PriusChat threads, other people who sign up seem to be able to find the stuff ok.

It was $46.83 officially from Toyota when I bought mine and it was still in print. So people are scalping it a little now that it's out of print. At $46.83 it has certainly paid for itself many times over, though in these online days if I lost it and needed it again I would probably spend the $15 on techinfo.

-Chap

 

ok well. I re traced me steps. and yes Chap. I was under the free manuals tab. my mistake.

I have managed to find the pages you have mentioned. I have also traced all relays and fuses to fill the diagrams. and ha e tested all for ohms... as well as checked voltages and amps at each terminal. all checks out.

is it possible that the switch is buggered?

when I turn the switcheck to the on position... I lose the DRLs and there is nothing but marker lights.



lights on are DRLs lights off is switch in on position.

make any sense to anyone else???

Thx guys.

 

Great, glad you found the manual. Hmm, maybe you could measure and post the voltages you find at the following places:

Ignition and headlight switches can be off:

• pull out the "DRL relay" (the small, plain relay in Engine Room R/B No. 3) and measure volts from pin 1 of its socket to ground.
• measure resistance/ohms from pin 5 of its socket to ground.
• put the "DRL relay" back in.

With the ignition and light switch still off, pull the headlight stalk toward you (the flash function). Any light from the headlights?

If no joy, use a friend or some string/bungee/whatever to hold the stalk pulled in the flash position, and measure:

• volts from IA1 pin 9 to ground (IA1 should be easy to get to after removing the driver side kick panel. Measure without unplugging, that is, use a thin backprobe into pin position 9 from behind, without separating the connectors.)

I could go on with a whole decision tree of "if X measured Y then go measure Z" but instead I'll stop here till we see what you get for these.

Cheers,
-Chap