Toyota GR86, 86, FR-S and Subaru BRZ Forum & Owners Community - FT86CLUB - Electronics questions for the nerds (techs) out there

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Electronics questions for the nerds (techs) out there

1 - I see in the system wiring diagram a "Option connector". In the system wiring diagram. It shows this as D29 and it appears to connect to the rear of the Head/NAV unit. This connector only has the CAN Bus, ACC power and ground on it.
Does anyone know what this connector is for? Does it give CAN bus access to the head unit for something or is it meant for future expansion/monitoring of the CAN bus?

2 - I read on one of the ECU flash threads that the ODBII connector (D10/DLC3) has more than just the standard system CAN bus. Supposedly it has another bus that is used for flashing the ECU. However the wiring diagram for the connector does not show any connections other than power (BATT pin 16 & IG2 pin 8), GNDs (pins 4,5) the CAN (H&L pins 6&14) bus, a 'headlight level' (LVL pin1) and a 'TC' line (pin 13) that runs to the ECM & Transmission control module.

So are there wires that hook up to that connector that are not documented in the system wiring diagram?

Part of the reason for question #1 is that I was wondering if we could add additional CAN bus sensors that could be read out by torque with the rest of the data. Perhaps an Oil Pressure sensor? I imagine that we could plug other sensors into the 'Option Connector' and their data could be read out on the CAN bus through the OBDII connector.

I am curious about the flashing BUS as well...

Quote:

Originally Posted by stugray (Post 1221817)

1 - Head unit needs vehicle speed/gear/handbrake position to deactivate features for safety (I believe its handbrake driven but not 100%)

2 - the J1962/OBDII connector must by comply with federal law and the documented OBDII parameters. Manufacturers are free to (and amost always do) make more available in either queryable or passive listen or write over that connector and CAN bus. The trick is having the equipment to actually read pure CAN and then decrypt the CAN messages into something useful. the OBDII protocol is effectively a limited API layered over the GT86 specific implementation of CAN.

man if my passenger could reprogram my navi while driving, i would be so happy. it also wont let me scroll my song list while moving :(