tewharaunz wrote:OK, I've done some more diagnostics, and it definitely charges when plugged in but not when it is running.
Does anyone know whether the key and the charging port use different circuits to activate the DC/DC converter?
Step 17: yes, voltage between E-03 (terminal No. 7) to earth is 13v
Step 18: yes, continuity between auxiliary battery and E-03 (terminal No. 7)
Step 18a: yes, with motor switch on, voltage between E-03 (terminal 8) and earth is 12v
Step 18b: yes continuity between A-08x (terminal 1) and E-03 (terminal 8) [Also on terminal 2 on A-08x]
Step 20: yes, continuity between C-106 (terminal No. 11) EV-ECU and E-03 (terminal No. 12)
Step 20a: yes, continuity between C-111 (terminal No. 116) and E-03 (terminal No. 4)
Steps 17 and 18 check that the 12V Hot All The Time supply to the OBC and DC Converter (DCC) is present and okay.
18a: checks that the key-switched 12V supply to the DCC is working, okay.
18b: checks the wire over which the supply of 18a is carried, okay.
18b: [Also on terminal 2 on A-08X] ??? what does this mean? That there was continuity to chassis?
20: checks wire that carries the enable signal for the OBC, okay
20a: checks the wire that carries the enable signal for the DCC, okay
So it seems that the wiring is intact.
My guess is toward something different in how the EV-ECU receives its power supply when charging and when going to READY.
The EV-ECU has a Hot All The Time 12V supply in addition to Switched 12V supplies. And it operates in different Modes to control functions of the car.
The DCC is a dumb box with no CAN control; it just needs the enable signal from the EV-ECU, called "DCSW" on the schematics.
i can imagine there is a diode-OR circuit in the EV-ECU such as shown here for the OBC block diagram [ 3 diodes can supply the 12V drive for the EV Control Relay]
that is also used for the DCC, although not shown in this diagram
If one of these diodes were blown open, then that could explain how the DCC works when charging but not when in READY.