ElECTRIC Karmann Ghia Project
Final Build & First Drive
December: The Final Push
It's getting cold and we realize we aren't going to be happy in this car without some heat. We ordered an electric heater kit from Canev, a Canadian company. Jason could have probably made it, but this way it actually got done.
Lots of wiring being done on the car at this stage. Heavy 0/2 cable from the front batteries through the transmission tunnel to the main fuse/disconnect switch under the back seat. More 0/2 cable from the rear battery box out the bottom of the luggage compartment and in again a short distance again under the back seat to a second main fuse and disconnect switch. Then from 0/2 cable from that fuse box, through the transmission tunnel to the other side of the back seat where our contactor box will live. In all we drilled 6 large holes in the transmission tunnel. Installing rubber grommets and wiring that large cable in such a tight space is not fun. From the contactor box more 0/2 cable run out the back towards the motor controller. In all this we found we were just short and wouldn't have enough wire to make all the cables we need, instead of getting potentially mismatch cable we vainly ordered more from EV West.
Other wires to run:
Control wires from the controller to the contactor box.
Throttle wires from the controller to the new Prius throttle pedal.
Communication wires between all the BMS modules.
CANBUS from BMS Display, BMS controller, Charge Controller, and Charger
Hall sensor mounted at the contactor box to BMS display to fuel gauge
3 position switch to contactor box to heater
Contactor box to DC/DC converter
Charge port to charger and charge controller
Plus all the contactors fuses and relays within the contactor box itself
Near the end of December all the wiring is done and we are ready for first turn on. Carefully make the final battery connections, turn on the disconnect switches, cross our fingers and turn the key……and the BMS isn't seeing all our batteries :(, time to remake all our BMS harnesses. At this time we realized the BMS harnesses we made were WAY too long, to clean up the installation we cut down each one and crimped new connectors on each one. That is over 60 additional crimps.
This process didn't take that long and 3 days later we turn it on and the wheels are spinning!!!! We did it, with a whole day left to spare in the year. Still need to program the controller and BMS and charge controller and charge up the batteries while we button some things up. Everything is looking good and really the whole process hasn't been too painful, the end is in sight.
January: First Drive
After doing some more checks and programming the charger we plug the car in and get it charging. The first couple charge sessions we are ensuring that it's monitored, I want to be sure the BMS cuts off the charger properly and prevents overcharging.
A couple more days and we get the seats in and get ready for the first drive. Take the car around the block a couple times and everything seems a little too good to be true. The only issue seems to be this strange thumping. Turns out one of the rear wheels was just barely held on, the lugs weren't tightened down at all, whoops, that could have been a disaster. The car was on jack stands so long we assumed we'd be taking the wheels off again for something.