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Pavlin Koev
Pavlin Koev, CERTIFIED TECHNICIAN
Category: Toyota
Satisfied Customers: 3483
Experience:  20 years hands on,Experience cars and trucks, gas and diesel
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Toyota Pickup: Have a 88 Toyota Pickup with wiring issue.

Customer Question

Have a '88 Toyota Pickup with wiring issue. First, would not start without jump start from another vehicle. This stopped working after a couple tries. Then I bump started it a few times. After it's last try it would not bump start and everything else electrical would not work. Relays are clicking very fast. Voltage drop across headlight relay grd reads 6+ volts. A few dash lights come on, and some that should'nt come on do (high beam indicator comes on when I try to use windshield washing fluid). Hazards did work but not flashers. Headlight circuit is not grounded anywhere, all 3 pins from headlight read battery voltage when relay worked. Please help, I am trying to get home for Christmas. Thank you in advance
Submitted: 4 years ago.
Category: Toyota
Expert:  Pavlin Koev replied 4 years ago.

Pavlin Koev : Hi and Welcome to Just Answer! My name is Pavlin and I will do my best to help.how old is the battery
Pavlin Koev : We.
JACUSTOMER-2p7jwny9- :

Not a battery issue. Replaced with another battery, voltage drop on headlight circuit is 6v+

Pavlin Koev :

Hi, is vehicle near you! have you tested body grounds?

Pavlin Koev :

do you have booster cable handy?

Pavlin Koev :

use booster cable to connect battery ground to chassis and battery positive to fuse box.

Pavlin Koev :

this way we will know if we have bad cable(s)

Pavlin Koev :

can you check and let me know please?

JACUSTOMER-2p7jwny9- :

Nothing changed, relays still flickering and no lights, hazards, starter motor etc...

Pavlin Koev :

in engine compartment fuse box you have fuse links, can you check there

Pavlin Koev :

Full Size Image

JACUSTOMER-2p7jwny9- :

No fuses or fusable links are blown.

Pavlin Koev :

ok what voltage at fuses and fusible links?

Pavlin Koev :

what voltage at alternator white wire?

JACUSTOMER-2p7jwny9- :

Haz/Horn shows 12.7

JACUSTOMER-2p7jwny9- :

Charge shows 3.6

JACUSTOMER-2p7jwny9- :

Will go check more, can't get headlight voltage due to relay flickering on/off

JACUSTOMER-2p7jwny9- :

Other side of charge fuse shows .3v - seems weird

Pavlin Koev :

ok, we have bad connection or corrosion there

Pavlin Koev :

hazard fuse is connected directly to battery

JACUSTOMER-2p7jwny9- :

All FL in engine bay show 12.65 to 12.7

Pavlin Koev :

ok check white wire at alternator

Pavlin Koev :

and white wire at ignition switch

Pavlin Koev :

ignition switch is supplied from alternator white wire

Pavlin Koev :

you can attach booster cable from battery + to alternator large terminal

Pavlin Koev :

this will by pass fuse box

JACUSTOMER-2p7jwny9- :

Alt. white wire is at 12.6v

Pavlin Koev :

can you use test light, this will be power test

Pavlin Koev :

volt meter can give you 12V

Pavlin Koev :

but there may not be current

Pavlin Koev :

do you understand?

Pavlin Koev :

test light must come ON bright.

Pavlin Koev :

if it is dim or not coming there is a issue.

Pavlin Koev :

volt meter can show 12V but light will not light up

JACUSTOMER-2p7jwny9- :

Ok, have test light

JACUSTOMER-2p7jwny9- :

attached booster cable to alt. and + battery, didn't affect voltage readouts at white ign wires or white alt wire

JACUSTOMER-2p7jwny9- :

which was 12.6 to 12.7

Pavlin Koev :

and test light is bright

JACUSTOMER-2p7jwny9- :

will re check with test light

Pavlin Koev :

ok

JACUSTOMER-2p7jwny9- :

Test light is bright for both

Pavlin Koev :

ok can you also check fuses in engine compartment

JACUSTOMER-2p7jwny9- :

I have only tested the fueses in engine compartment, I will go check fuses in driver side kick panel

JACUSTOMER-2p7jwny9- :

should I use test light, dmm, or both

Pavlin Koev :

ok also check body and engine ground

Pavlin Koev :

connect test light to Bat+

Pavlin Koev :

and probe engine block and body sheet metal

JACUSTOMER-2p7jwny9- :

I have forgot to thank you for your time, hopefully we can fix this and you will be paid

JACUSTOMER-2p7jwny9- :

I will go check body and engine grounds with test light

Pavlin Koev :

lets get it fixed first, thank you

JACUSTOMER-2p7jwny9- :

Body and engine grounds seem fine

JACUSTOMER-2p7jwny9- :

Will check kick panel fuses

JACUSTOMER-2p7jwny9- :

I has to scrape at the body ground to get a decent connection

JACUSTOMER-2p7jwny9- :

*had

Pavlin Koev :

ok that is notmal

Pavlin Koev :

so when ignition is turned ON what happens

Pavlin Koev :

are all light on or not

Pavlin Koev :

do you hear starter relay to click?

JACUSTOMER-2p7jwny9- :

The dash lights that come in when key is turned to on are charge light and brake light, oil pressure light had come on and does not now

JACUSTOMER-2p7jwny9- :

starter relay or start itself will click but nothing else

JACUSTOMER-2p7jwny9- :

stop light fuse with brake pedal pushed in does not get test light to come on

Pavlin Koev :

ok lets work on the starter first

Pavlin Koev :

there is black wire going to starter solenoid

Pavlin Koev :

not the large cable going to battery

Pavlin Koev :

a smal wire connected to small terminal of starter solenoid

JACUSTOMER-2p7jwny9- :

tail light fuse removed allows hazards to come on but no 12v at fuse

JACUSTOMER-2p7jwny9- :

I have tried to jump the wire going to solenoid

Pavlin Koev :

this wire must have voltage, or your test light must come on when key is in start position

JACUSTOMER-2p7jwny9- :

I believe 12v is going to it when switched on

JACUSTOMER-2p7jwny9- :

I will go check, or attempt to, I do not have any help

Pavlin Koev :

NO only when key in start position

JACUSTOMER-2p7jwny9- :

oh, when in start position only

JACUSTOMER-2p7jwny9- :

ok

JACUSTOMER-2p7jwny9- :

I will check

Pavlin Koev :

you can bridge starter relay

JACUSTOMER-2p7jwny9- :

should I disconnect the connector going to the relay and test this for voltage?

Pavlin Koev :

relay is passing the voltage to the wire when click as key is turned to start position

Pavlin Koev :

you can power up this terminal on the relay directly from bat+

Pavlin Koev :

just briefly to check starter reaction

Pavlin Koev :

or use separate wire and touch briefly that solenoid terminal to battery+

Pavlin Koev :

starter must turn, if not, there is problem with cable from battery to starter or starter is bad

JACUSTOMER-2p7jwny9- :

ok, I will try to bypass the relay momentarilly

JACUSTOMER-2p7jwny9- :

I had voltage from two black wires going to the start relay when in the start position

JACUSTOMER-2p7jwny9- :

I am not sure which wire I need to jump, not easy to trace solenoid wire from starter to starter relay, will check schematic

Pavlin Koev :

I need to step down fro 30 minutes, can please wait for me

Pavlin Koev :

go directly to one on starter

Pavlin Koev :

you use ohm meter to check which one of the black wires is going to starter

JACUSTOMER-2p7jwny9- :

I should be around in 30mins, it is getting late where I am and cold. The starter is trying to turn with key in start position, it will not turn the motor over though.

JACUSTOMER-2p7jwny9- :

I bypassed the relay and it tries to turn the motor but no luck, sounds like a weak battery.

JACUSTOMER-2p7jwny9- :

Crankshaft spins when turned with socket

JACUSTOMER-2p7jwny9- :

Starter was tested off of the vehicle at an auto parts store and tested good

Pavlin Koev :

is there a way you use this booster cable between starter and battery +?

Pavlin Koev :

if you by pass starter cable and starter works, problem is in the cable, if starter still not working, you have bad starter

JACUSTOMER-2p7jwny9- :

I just realized after fully tightening the neg. battery terminal it was not fully clamped on the post. I will try to have that fixed tomorrow morning. I will be able to do more testing about 16 hours from now. Thank you so far for all your help

Pavlin Koev :

ok, have a good night

JACUSTOMER-2p7jwny9- :

I'm back, you around?

Pavlin Koev :

Yes hello

JACUSTOMER-2p7jwny9- :

ok

JACUSTOMER-2p7jwny9- :

I will check neg cable to battery and use jumpers to go from starter to + battery

Pavlin Koev :

okay

JACUSTOMER-2p7jwny9- :

Neg cable is ok, jumpers didn't help, sounds like weak battery, will check battery

JACUSTOMER-2p7jwny9- :

still have other problems with headlights

Pavlin Koev :

if battery is bad, must replace

Pavlin Koev :

bad battery can cause many troubles

Pavlin Koev :

if you have battery from another vehicle, use it for testing

JACUSTOMER-2p7jwny9- :

I will see if I can find another battery

Pavlin Koev :

okay

Pavlin Koev :

I will step out for couple of hours

Pavlin Koev :

will check back with you when back on line

JACUSTOMER-2p7jwny9- :

Sorry, I could not fix it on my own or with your help. I had a mechanic who was very good with electrical come out to work on it. It took him 2 hours of diagnositcs and such.

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