I have a 1984 subaru brat. Rebuilt engine, new distributor, new coil pretty much all new. No matter what i do when i turn the key i get no interior power.... The thing cranks with no spark and all that works is my hazard lights! If i run a jumper wire from the + on the battery to the + on the coil i have power on everything and weak spark and not the full voltage i need, and the power is constant even when the key is off EVERYTHING stays illuminated and on inside. Could someone please tell me what i need to look for here? i am completely out of ideas. I know its gotta be a wiring problem but i just dont know where to begin.

 

Second question. What is the yellow and white wire that runs from the coil to the computer, whats its purpose? 

 

Thanks in advance

Nothing jumps out to me of what could be the issue, but like thou say, a wiring issue. If the issue wasn't there before, then it's something you caused.

 

The coil wires get easily reversed when coils are removed, causes problems. I tagged mine. I don't know how you can't get power once you turn your key? There are relays, but everything should power up or pop fuses if crossed... hmmm...

 

Running a jumper has just created a different path/avenue for power to flow so it will cause different then normal events. If it was working correctly before, it's out of its correct configuration. Step back, sleep on it, check again. I love my 84 roo, never had an issue like this.

 

sorry I am no real help.

Edited October 23, 201510 yr by Indrid cold

Its something like that. my brat came from a junk yard and was really unloved i have never had it started before so i am just going foward step by step its tricky. Yeah there is now power without that jumper wire i have worked on subies for a long time and this is just some whole new kind of thing i have never seen before! 

Edited October 23, 201510 yr by antond141

Next to the battery there is a rectangular grey box. Pop the grey cover off and check the three wires inside.

Already checked all the fusible links and they are all good to go but still no power or spark when it cranks, all that happens is the starter runs. none of the accessories come on and there is no spark. 

The wire thin wire from battery (+) to the fuseable link box needs to be removed and inspected, especially where it connects to the fuse block. Could be a bad ignition switch, its mote likely you have a damaged wire somewhere but since you have to get to the connector for testing anyways might as well test it first.

The yellow wire you asked about is connected to the (-) terminal on the coil? Did you trace it to the ecm under the dash?

Sounds like a bad ignition switch.

 

The wire io the ECU provides a RPM signal.

ah ok i thought maybe it could be the switch but i was not sure since it still cranked and there was somewhat power. But thats a good place to start.