Wiring Question

[money pit]

When wiring accessories such as A/C, radio, or after market gauges, do you ground the accessories to the dash or firewall? Or, do you go directly to the ground on the battery? What about the power side, do you connect to the battery or run a single wire into the interior. I have a auxiliary fuse panel that has constant power and accessory power. I'm trying to clean up my engine compartment since I have a lot of wires from the interior going to the battery or a distribution block. Thanks

 

[Chryco Psycho]

Any good clean ground will work such as the dash frame or you can use a bus & attach all of the grounds to that & run a single lead out to a good ground point .
For power I would run to the battery terminal on the start relay to feed the aux fuse panel or dist block under dash with a fusable link .

 

[Challenger RTA]

Very vague description. pictures or a diagram shows what you have.you ask,"do you go directly to the ground on the battery?" Yes and No. in general yes. 99.9% what Chryco Psycho said is in general true.Depends on current draw of all the load. You could have it wired a number of different ways. An other thing acc are a switched power. The ign switch and wiring and firewall connectors can only carry a limited load. In short there are grounds.1 bolts to the motor.ground for starter. somewhat isolated to motor. 2nd is the chassis ground by the battery for all other loads. if anything I would upgrade ground there. Calculate you load see if it is acquit. You have a auxiliary fuse panel that has constant power and accessory power.It should be protected at the battery or stater relay where ever it's connected. I would feed through the

Windshield Washer Hose Firewall Grommet. That's what I would do.​

 

[money pit]

Very vague description. pictures or a diagram shows what you have.you ask,"do you go directly to the ground on the battery?" Yes and No. in general yes. 99.9% what Chryco Psycho said is in general true.Depends on current draw of all the load. You could have it wired a number of different ways. An other thing acc are a switched power. The ign switch and wiring and firewall connectors can only carry a limited load. In short there are grounds.1 bolts to the motor.ground for starter. somewhat isolated to motor. 2nd is the chassis ground by the battery for all other loads. if anything I would upgrade ground there. Calculate you load see if it is acquit. You have a auxiliary fuse panel that has constant power and accessory power.It should be protected at the battery or stater relay where ever it's connected. I would feed through the

Windshield Washer Hose Firewall Grommet. That's what I would do.​

View attachment 98004

The grounds are for the after market gauges, the lighting for the gauges, tach, radio, gas tank sending unit, and the lights for the after market AC. The defrost/heater/AC motor is grounded to the firewall. The power side is to power the aux fuse panel. This goes directly to the battery (per instructions). The power for the defrost/heater/AC also goes to the battery (per instructions). I bypassed the ammeter, so I have a couple of 10 g wires going to the alternator. I also used the windshield washer grommet to run the wires through the fire wall. Thanks