02 Tundra ign fuse short

I have a 2002 tundra(v6/manual trans/4wd/SR5). I have a crank/no start problem. When I turn the key to on position the 5a ign fuse and 15a acc fuse both blow immediately. By disconnecting the power outlets on the dash I was able to stop the acc fuse from blowing but the ign still does. I've checked condition and function of all other fuses and relays and they're all good.

The vehicle ran/started fine when I parked it a few months ago. I've inspected everything I can for bad/broken/shorted wiring, rodent damage, and bad grounds, but found nothing. I was hoping someone would have access to the wiring diagram with the 5a ign fuse circuit that also showed the other components in that circuit so I could test and trace. Any other suggestions would be appreciated. Thanks all, cheers.

-A

 

A link to the electrical wiring diagrams is in the 4th/5th paragraph of this thread: https://www.tundras.com/threads/so-you-wanna-buy-just-bought-a-1st-gen-tundra-eh.115928/

I have no idea what could be causing it, other than, obviously, something is shorting. But not knowing where you are so we understand what elements may be at play, plus what's been done to the truck in general it's tough to say if it'd be a corrosion issue, or what. But the fact it starts when you turn over the truck ... I'm guessing something on the IGN circuit, that would be engaging with the relay, whether that be the neutral safety switch having a short, starter arc'ing to ground, or whatever.

 

If your able to find the EWD link shift linked to, these will be the circuits assoc with 5A IGN fuse.
Good luck....finding a short to ground can be tedious but feel with the EWD you'll be able to check the circuits methodically.

 

Hey man i have the exact same problem with my 2002 v8 tundra. Did you happen to ever find a solution. Im chasing my tail on it. Thanks

 

Like so many strangers making it here from the internet with "1st interaction with the community is a problem instread of a hello", @brunoaustin hasn't logged on since he made this post. My guess is, one of the last two posts helped steer him to the solution, but we will never know what it is, because he never followed up. We see both here, a lot. I tagged him here with hopes he gets an email alert and can hop in to let us know what happened. Don't miss that link in my reply above. There's a ton of technical data at your fingertips in the first links of that thread I provided a link to.

​

 

Ok awesome thanks. Yeh im not too familiar with how these threads work. I just recently bought this truck and had to spend alot of money on it already with timing issues and rack and pinion replacement and it ran good now this. Im not trying to spend anymore money at the moment so trying to hunt it down myself. Hoping someone has had the same problem and could give some insight. Im not an electrician by any means lol

 

Totally get it. That thread I linked in reply #2 above, that's your index to a wealth of info our community has assembled to help with these trucks. The links near the top of that thread will connect you with service manuals, wiring diagrams, programming booklets, all kinds of stuff.

@BubbaW's picture above is taken (I believe) from the EWD (electrical wiring diagram) which literally gives you ever circuit attached to the IGN fuse, and you can look in that manual to see what color the wire is and trace it back.

Like, "Combination meter" is your gauge cluster. Did you change any bulbs recently?

Or "Charging" would be your alternator/power circuit, did you do anything with those wires recently, OR has the battery ever been corroded? Internal corrosion will cause shorts and wires to heat up, which blows fuses. These trucks are notorious for corrosion inside the cables. Try pulling and cleaning the terminals. You get the idea, I hope.

It's tough on stuff like this, because we don't fully know what you did with the truck recently, 50% of the time on here, something someone recently did for maintenance caused the issue, like how people are ignorant to wire routing for the crank position sensor and cam position sensor when doing the timing belt, and the harness (misrouted) gets nicked by a belt or pulley. And we don't know whether you have the V6 or V8. We don't know if you've used auto parts store parts, especially for mechanical stuff on these trucks, like if you put in a parts-store alternator vs. OEM (Denso) brand, that could explain it, b/c parts store parts are utter shit these days, certain electronic/electrical parts on these trucks you shouldn't use anything except the OEM brand. There's quite a few unknowns we're working with here. Pictures of the engine bay and front of the engine can help sometimes too.

 

I have a 2002 v8 tundrA 4x4. I will start looking through those wiring diagrams thats alot of helpful info yall have done alot of work on listing all that! Thats awesome. I unhooked the alternator today and turned key and it still blew fuse so i eleminated that and tried to look at all the connections around the timing belt housing where i just had it worked on didnt see anything noticeable. I have recently put in a new bulb in the done light inside. And had the timing messed with. But thats about it that i know of ive only had the truck for a month and its been one thing after another. It ran great when i got timing right for a few days. But seems battery is about done or something is pulling it down not sure gonna be a pain to find its looking like‍♂️ would any bad relays possibly be an issue ive read a few
Things saying that. The relays that are on the IGN and ACC fus that it popping of course! Thanks for all the help so far!!