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Re: Bad electrical screw-up on 89 PU
On Sun, 2 Apr 2006 11:43:01 -0600, "JensenC" <farview at frontier dot
net> wrote:
[color=blue]
>As we all know, electrical problems really suck, and I don't know how bad
>this one is yet.
>
>Background story: I plugged a jingus Chinese made cell phone adapter into
>my cigarette lighter but the LED didn't indicate power. A few moments later
>smoked pour out the socket and I jerked it out to find melted plug while
>sniffing burning plastic.[/color]
I'm guessing reversed polarity here, or a seriously screwed up
adapter. This is why you avoid buying things you can't trace the
heritage for - the Chinese copy everything and make the cheapest
versions possible. And the cheap copies often don't have the usual
UL-style safeguards like polarity protection, over-voltage crowbar
zeners or fuses - so when they fail, it's often catastrophically.
Consider yourself lucky that the adapter didn't blow up your
cellphone while it was going up in smoke. Sending +/-12V down the
OUTPUT wire meant for +5V could do it.
[color=blue]
> Then I noticed the guages and tach not working.
>Also no turn signals or radio. The truck was still running and i pulled
>into Walmart (more Chinese crapola) in case I needed fuses. Hesitate-
>should I turn off the engine or not. I did, then turned the key to start -
>dead. Push started the truck and headed for home as darkness fell. Turned
>into driveway and truck died - the battery kept it alive to that point.
>Winched it into garage.
>
>What I found: No fuses blown. Inspected fuses in main engine compartment
>box and the fuse/relay block on left foot well wall. Cigarette lighter had
>been rewired (previous owner?) directly to battery power thru the hot
>terminal of an unused relay socket clipped onto the fuse block. The wires
>from this socket enter the wiring harness going up into the dashboard. I
>removed the fuse/relay block and opened it to inspect. It appears ok - all
>traces inside are intact.[/color]
First things first: If you can track down the last owner, and
you're sure that he's the idiot that did this, I'd go talk to Vinnie
Bombatso and the local Wise Guys and get his kneecaps broken. ;-)
I'd say get him whacked, but that night be a slight overreaction - if
you cause permanent pain it'll be a daily reminder of what not to do.
If you hotwire the lighter socket on your own car, take out the
fuse, and get the polarity backwards... you deserve what happens next.
But to sell the car and leave that nasty little surprise there for the
next owner to find is way beyond mere stupidity.
[color=blue]
>What now: At this point I decided to take a break and consult this group to
>see if anyone has tips or insight to troubleshooting a problem like this.
>Is there a fusible link or weak point in the wiring bundle? Do I need to
>find the electrical schematic for my VIN number? The only thing I can think
>of is to remove the dashboard and instrument panel and begin unwrapping the
>wire bundle. I can't really test with an ohm meter because I don't know
>which terminals or wires should have continuity to another point or ground
>(except for obvious ones).[/color]
First things first: Go get a repair manual. The Toyota factory
manuals are much better than the aftermarket, but they are NOT cheap,
they're priceless. The Haynes and Chilton books will work, but do not
take their wiring diagrams as gospel - they don't have access to the
factory blueprints, they draw their own and don't always get it right.
You can figure this out yourself if you attack it methodically, but
you need a diagram as a roadmap, to see where the power is supposed to
go and not go.
Sounds like the first thing to check are all the Fusible Links -
they're the rubbery wires with the special ring terminals with molded
boots that connect to the Battery + terminal stud, and about 6" later
there's a molded-over splice as they connect to the main harness
wires. If you pop one of those you lose the alternator charge line
too the battery, as well as a bunch of other things you noticed dead.
And there are a half-dozen fusible links feeding different systems,
one goes straight to the EFI Computer so it theoretically can keep
running with several other fuses or links failed.
(There are special terminals and overlap barrel crimps, and specific
splicing instructions for fusible link wire - follow them to the
letter, or it pops at the splice and you'll have to do it over...)
And after you solve the immediate problem of getting the alternator
charging again and all the gauges back on, follow the diagram and put
the damned lighter socket wiring back the way it's supposed to be -
switched power through an Accessory relay in the fuse & relay center,
and through a 10A (most likely) to 15A fuse in the fuse block
Having the lighter socket switched with the key is a safety feature
so someone or something can't trigger the lighter unattended and light
the car on fire - it has happened. There is also a safety thermal
fuse on the back of the lighter socket that may have been blown and
bypassed, take the socket out and look for a big glob of solder back
there.
If you need a real always-on high current accessory socket in the
cab for an inverter or computer power, go buy a real add-on accessory
socket at an auto parts - and it will NOT have the bimetal clip in the
back of the socket needed to run a pop-out lighter element off of.
Run a seperate 12-gauge or 10-gauge lead from the socket up to the
battery, and put an inline fuseholder to the master +12V battery stud.
12-gauge wire is good for 20A conservatively, and 10-gauge for 30A.
You want the fuse to blow before the wire, so conservative is good.
--<< Bruce >>--
--
Bruce L. Bergman, Woodland Hills (Los Angeles) CA - Desktop
Electrician for Westend Electric - CA726700
5737 Kanan Rd. #359, Agoura CA 91301 (818) 889-9545
Spamtrapped address: Remove the python and the invalid, and use a net.
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