electrical help - fan, horn, blinkers, temp

[sandasharpe]

Don't forget the mounting bolt on the horn bracket to radiator support. The mechanic doing the raodworthy on mine stuffed around for an hour and declared there must be something wrong with the new horn he'd just fitted. Fixed it by tweaking up the mounting bolt some more.

Sometimes it is that easy!!

[Vombil]

update: I've made a nice thick -VE battery cable and earth to rad support. I've also used contact cleaner on all major elec connections. NO CHANGES!!!

However i've since noticed with ignition on (car not running) that I have no earth at the coil. I tested my HQ and had 5V and my other ute with elec ignition, that had 9V. This seems strange as the car starts and runs like a dream.

Also there does not appear to be a good earth going to the starter motor (ign on, not running). The starter itself seems earthed. This may be related to the coil or maybe it doesn't earth until its cranking??? i know nothing about this shit!

I will test the old mans WB to see if it's any different.

Then i'll change coils.

Then i'll try another neutral safety switch.

Then.... that's it. It'll be time to ring in the pro's!

[Spike]

Geez mate car electrics.......what a pain

[Big Rob]

Keep going.... you'll get it and then have knowledge about the whole thing and how it works.

[agr071]

update: I've made a nice thick -VE battery cable and earth to rad support. I've also used contact cleaner on all major elec connections. NO CHANGES!!!

However i've since noticed with ignition on (car not running) that I have no earth at the coil. I tested my HQ and had 5V and my other ute with elec ignition, that had 9V. This seems strange as the car starts and runs like a dream.

Also there does not appear to be a good earth going to the starter motor (ign on, not running). The starter itself seems earthed. This may be related to the coil or maybe it doesn't earth until its cranking??? i know nothing about this shit!

I will test the old mans WB to see if it's any different.

Then i'll change coils.

Then i'll try another neutral safety switch.

Then.... that's it. It'll be time to ring in the pro's!

If it still has points in the dizzy, you won't see an earth till the points are closed.
Did you do an earth to the starter or just the rad support? (Rad support doesn't need a real thick one as it's the earth for gauges/lights etc. whereas the starter can draw 300 to 400 Amps hence why this one has to be thick).

- - - Updated - - -

Also, can you just give a refresher of what doesn't work now, without going into detail as to what you've done please.

[Vombil]

thanks Agro

still Not working
- horn
- washer (this may just be pump)
- heater fan
- reverse lights
- handbrake warning light ( dummy lights work as charge light comes on with ignition)
- temp (this fluctuates between .2V and 9V odd with ignition on. my HJ has 12V constant
- oil warning - does not come on with ignition

i have not earthed starter. I put a larger cable on starter > +ve batt and larger cable for earth to alt > battery

it is electronic ignition (aftermarket bosch)

i just checked the old boys WB 6 banger. There is also no earth at coil with ignition on, not running.

A concern of mine is that there is no earth for instruments at coil as per VB -VH diagrams i've looked at.

It's a HZ 253 in a WB with wb 6cyl auto harness running elec ignition.

[Dr Terry]

Go back to basics first.

You need 4 cables to the battery as a minimum.

1. Thick cable from +ve battery terminal directly to the starter.
2. Thinner cable (6mm) from -ve battery terminal to the alternator output
3. Thick cable from -ve battery terminal directly to a bolt somewhere on the engine on head. From memory, the original V8 earth cable used a bolt at the alternator bracket.
4. Thinner cable (6mm) from -ve battery terminal directly to a good body bolt. I think the original went to a radiator mount bolt or the radiator support panel itself.

The 2 thick (heavy) cables only carry starter motor current, the other 2 carry the current for the other stuff (lights, relays, instruments, heater fan etc.).

As agro71 has said, the coil voltages will vary depending on whether it has points (& whether they're open or closed). If it has electronic ignition &/or a ballast resistor the voltages again will be different.

Dr Terry

[Vombil]

Go back to basics first.

You need 4 cables to the battery as a minimum.

1. Thick cable from +ve battery terminal directly to the starter.
2. Thinner cable (6mm) from -ve battery terminal to the alternator output
3. Thick cable from -ve battery terminal directly to a bolt somewhere on the engine on head. From memory, the original V8 earth cable used a bolt at the alternator bracket.
4. Thinner cable (6mm) from -ve battery terminal directly to a good body bolt. I think the original went to a radiator mount bolt or the radiator support panel itself.

The 2 thick (heavy) cables only carry starter motor current, the other 2 carry the current for the other stuff (lights, relays, instruments, heater fan etc.).

As agro71 has said, the coil voltages will vary depending on whether it has points (& whether they're open or closed). If it has electronic ignition &/or a ballast resistor the voltages again will be different.

Dr Terry

for battert ive got 2 on the -ve and 2 on the +Ve

neg thick to alternator block bolt, neg thinner is to rad support

pos is 1x thick to starter and 1x thinner to alt input? There is a earth?? ( a very thin black wire) that comes out of the back of the alt (separate to thicker input) and runs back towards the starter and into the loom near firewall.

so i have 4. but not a -ve from batt to alt output

[wbute]

the electrics on the engine are earthed through the earth on the alt(remember that the engine is insulated through the engine mounts and gearbox mounts otherwise). All the other electrics are earthed via the body through the little earth on the rad support.
I think you will find that the other dash problems are through a bad earth in the dash somewhere.
You mentioned something about changing the reversing light wiring earlier. As soon as you start changing stuff you open a can of worms.
Retrace your steps and you might find the issue.
My other sugestion is forget about voltage readings and go back to basics. Use a test light and just follow the principle that 12 volt electrics are simple. You only need two wires, earth and positive. Find where one of these two are missing using the test light.
Always check the test light is actually earthed too! This can catch you out!

[Vombil]

anyone know of the clip that holds the harness onto the bulkhead frame doubles as an earth?

i swapped pretty much everything. the netrual safety switch was totally stuffed so i replaced it and it was working.. monumentality. I changed the indicator/horn contact mechanism trying to fix the horn and yeah, maybe set off the safety switch again.

ive run an earth direct from battery to harness earth on a-pillar trying to earth the instruments better. no improvement.