T8 (USA) Rear Fuse Box - Adding a new circuit
After hardwiring my Radar Detector & DashCam to the passenger-area fuse box, I decided to have a look at the rear (cargo) area fuse box. The passenger area fuse box was completely populated, even for features not installed in my car. The rear fuse box, however, wasn't. Only circuits actually installed in the car are fused; the other positions are blank. That doesn't keep you from using these unused positions, however, so if you're interested in learning a quick way to add a 5/10/15A circuit in the cargo area, like for a rear-facing DashCam, read on - I might save you some time.
First, here's the fuse reference from the owner's manual:
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Second, here's an annotated picture of the T8 (USA) Rear Fuse Box, showing installed fuses, which contacts are hot during following ignition (RED squares), which contacts are "always" hot (PINK squares), and which contacts in the fuse slots have no metal contact (YELLOW "X"):
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Finally, this last picture shows how to properly install the Lumision FuseTap into position #24 (Ionic Air Cleaner), resulting in a now useful circuit that follows ignition:
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Some ideas for using this circuit:
Anyway, hope that this info saves someone some time.
Cheers,
SonarTech
After hardwiring my Radar Detector & DashCam to the passenger-area fuse box, I decided to have a look at the rear (cargo) area fuse box. The passenger area fuse box was completely populated, even for features not installed in my car. The rear fuse box, however, wasn't. Only circuits actually installed in the car are fused; the other positions are blank. That doesn't keep you from using these unused positions, however, so if you're interested in learning a quick way to add a 5/10/15A circuit in the cargo area, like for a rear-facing DashCam, read on - I might save you some time.
First, here's the fuse reference from the owner's manual:
- Heated rear window 30A
- Power rear seat (driver side) [Excellence] 20A
- Pneumatic suspension compressor 40A
- Rear electric heater (passenger side) 30A
- Empty
- Rear electric heater (driver side) 30A
- Power rear seat (passenger side) [Excellence] 20A
- Empty
- Power tailgate 25A
- Power front seat (passenger side) module 20A
- Trailer hitch control module 40A
- Seat belt tensioner module (passenger side) 40A
- Internal relay windings 5A
- Empty
- Foot movement detection module for opening the power tailgate 5A
- Empty
- Empty
- Trailer hitch control module 25A
- Power front seat (driver seat) module 20A
- Seat belt tensioner module (driver side) 40A
- Parking camera 5A
- Empty
- Empty
- Ionic air cleaner [Excellence] 5A
- Feed when ignition is switched on 10A
- Airbag and seat belt tensioner modules 5A
- Cooler; heated/cooled cup holder (rear) [Excellence] 10A
- Heated rear seat (driver side) 15A
- Empty
- Blind Spot Information (BLIS) 5A
- Empty
- Seat belt tensioner modules 5A
- Emission system actuator 5A
- Empty
- Empty
- Heated rear seat (passenger side) 15A
- Empty
Second, here's an annotated picture of the T8 (USA) Rear Fuse Box, showing installed fuses, which contacts are hot during following ignition (RED squares), which contacts are "always" hot (PINK squares), and which contacts in the fuse slots have no metal contact (YELLOW "X"):
Finally, this last picture shows how to properly install the Lumision FuseTap into position #24 (Ionic Air Cleaner), resulting in a now useful circuit that follows ignition:
Some ideas for using this circuit:
- 12V Power Outlet that turns off with the car
- Inverter for the rear seats, you know, like the one Volvo promised me would be installed in my T8 that WASN'T...
- Additional external lighting effects
- Hardwired rear-facing DashCam
- Chilled (or heated) box for food, drinks, grocery, etc...
- Magnetohydrodynamic Drive module
- Flux Capacitor
- Turbo Encabulator
- Incinolet Electric Toilet
Anyway, hope that this info saves someone some time.
Cheers,
SonarTech
