Disabling the DC-DC converter?

[RobertSmalls]

I'm looking for the DC-DC converter's "off" switch so I can deep cycle and grid charge my 12V battery.

What happens if I cut wire B3 on the DC-DC converter module? The electrical manual calls it "IGA" - ignition for the IMA system.

If that's the correct wire, then I'll run it through a relay tied to a toggle switch on my dash. That toggle switch will be mounted next to a permanently-installed voltmeter.

[MN Driver]

I'm nowhere near my service manual but I think there is a fuse that might disable it if pulled. Looking through the diagnostics there is a part where it says something like 'check fuse #xx and check voltage at pin x of the connector.' That might clue you in on the proper connection to switch. Based on the amperage required, you might need to have your switched connection to a relay controlling that circuit though.

[Hybrid-Battery-Repair]

Disconnect the plug in step 15: Honda Insight (2000-2006) - Hybrid Battery Removal

Originally Posted by RobertSmalls

I'm looking for the DC-DC converter's "off" switch so I can deep cycle and grid charge my 12V battery.

What happens if I cut wire B3 on the DC-DC converter module? The electrical manual calls it "IGA" - ignition for the IMA system.

If that's the correct wire, then I'll run it through a relay tied to a toggle switch on my dash. That toggle switch will be mounted next to a permanently-installed voltmeter.

[RobertSmalls]

The high voltage input? Well, that would kill the DC-DC, but I want something I can toggle on and off from the dashboard. I think I'm going to cut the wire I mentioned and see what happens.

[Artric]

Am I reading this right that you want to run the high voltage wire to a switch on your dash... wouldn't you need a really high power switch and to take a ton of precautions? Sounds dangerous...

[3-Wheeler]

Artic,

The control module in question has low level voltages, and won't present a hazard when routed to the dash.

Jim.

[Mike Dabrowski 2000]

I found that the best place to turn the DC/DC converter on or off is the Inhibit pin, which is how the FAS board enables or disables the DC/DC.
Pin A27 on the MCM connects to pin 6 on the DC/DC (DVINH).
http://99mpg.com/Data/resources/down...d_play_fas.pdf
The FAS 2 relay opens the wire to enable the DC/DC when in FAS, and if I remember correctly the MCM disables it by bringing it high (5v).

[RobertSmalls]

Thanks, Mike, that does seem like the elegant way to turn it off. I learned by trial and error, the DC/DC converter puts out 5V on pin 6, and you short it to ground to inhibit.

I cut the MCM's DVINH wire, so it's all manual now. The DC/DC converter still reports its temperature to the MCM, which can run the IPU fan, but I don't know if the DC/DC's overheat shutoff logic is internal, or inside the MCM. Nor do I know if a DC/DC converter has ever overheated with the IPU fan running.

I bet you can run the DC/DC without the key in the ignition, for one-plug grid charging. I figure if you energize DC/DC pin 1 (IGN) and the HV contactor relay, it should start charging. You'd also want to either boot the MCM, or run the IPU fan continuously.

Speaking of the HV contactor relay, do you have to energize that to grid charge anyway?