Help! TA22 Wiring Problems!!

**sillycar chick** · 20-03-2006, 08:33 AM

Putting a long story short... mech fuel pump died, fitted electric, being bodgy and lazy tapped power off back of heater/gage fuse on panel (just a temporary arrangement), fuel pump working but started driving to notice had no guages or heater! But fuel pump still working..... ????

When I got home, I tested fuse panel with light, there is power out of each wire from the fuse, so I would guess the earth is ok, there is power to the fuse, but no power running from fuse to guages or heater unit? I have just printed off two pages of wiring diagram courtesy of Classique71, but I am hopeless at wiring and cant read diagrams too well....

So can anyone help? I dont really care if I have to be bodgy temporarily and run a wire directly from the fuse to the guages (if possible) to over-ride the part that is obviously giving me trouble...

So come on, wiring gurus, i need yous!! .... I am not too happy about it right now, it was supposed to go on the dyno today to sort out the carbies, but there is no way I am driving for half an hour without a temp guage or thermo (which I havent fitted yet). Thanks!

**sillycar chick** · 20-03-2006, 03:55 PM

Someone please help.... I need my car

**Invid** · 20-03-2006, 07:04 PM

Probably a stupid question but have you checked that the fuse isn't blown? The fuel pump could be overloading the circuit. As Electricity will take the path of least resistance it may be chanelling all the power to the pump and out to earth, rather than trying to go through a blown fuse...

**crownv8** · 20-03-2006, 08:24 PM

Short answer is disconnect the fuel pump and change the fuse and see if the heater/gauges start working again. Make sure you change the fuse as they can blow at the very end where you can't see a break.

Don't jump a wire straight to the gauges as they should run a voltage stabiliser. Basically that reduces the voltage that the gauges get to about 7 volts. Put 12 volts in and they will definately be on the blink.

You may need to get a power feed for the fuel pump direct from the back of the ignition switch and put in an in-line fuse of 15amps. Usually you will be looking for a black wire with a yellow trace. (most common toyota colour for ignition feed)

Other than that I would really need to see the car.

**BradW** · 20-03-2006, 09:24 PM

Probably best to run the fuel pump off a relay too.

**Squid** · 20-03-2006, 09:59 PM

mmm yes relays are your friend

**sillycar chick** · 20-03-2006, 10:15 PM

Originally Posted by Invid

Probably a stupid question but have you checked that the fuse isn't blown? The fuel pump could be overloading the circuit. As Electricity will take the path of least resistance it may be chanelling all the power to the pump and out to earth, rather than trying to go through a blown fuse...

Fuse I have checked, not visibly blown, and if it was blown and you couldnt see it, you wouldnt be getting power off both ends of the back of the fuse panel??? And I had already disconnected the pump completely off the system and checked it wasnt draining too much power... obviously didnt fix it.

I am planning on running the fuel pump with manual switch and relay, but the pump shat itself sun arvo and it was supposed to be on the dyno mon morn, so I figured I could do it properly later, just had to get it running.

But anyway, I think I have upset something in the wiring somewhere which wouldnt be hard considering the mess it has been in since I bought it. Just hoping someone knows how its setup from fuse panel to guages so I can try to find it and see if I can find a fault.... bloody wires!!

**tricky** · 20-03-2006, 10:52 PM

OK. First up, get some paper and a wiring diagram. Forget everything you have determined thus far.

Check the fuse continuity with a multimeter, then check for power to the fuse block with the ignition switch in desired position. Confirm power is leaving the back of the fuse box (assuming this is where you tapped power from. You could have knocked the bugger.) If you have a reading here, it's time to pull the instrument panel out. It's really not that hard to do! The things on this circuit are your reverse lights, your blower and all of your gauges. If the blower/instruments have failed but the reverse light still works, well, you know exactly where to start looking.

Basically, be systematic and write everything down. Since the blower and instruments are out, it is highly suggestive that either the fuse or the connection at the back of the fuse box are stuffed. Good luck

Electrics can be a BITCH!