Help! Almost didn't make it home! (2000 Insight)

[BabyDiesel]

Long story short, coming back home from picking up my buddy from military base, my 12v battery voltage dropped from 12.1 to 8.5

What should I do so I can keep driving my Insight???

I found this on Insight Central:

"Replace the 12V battery or charge it up and disconnect the three connectors on the BCM(circled in red). This will force your DC-DC converter to stay on. Then you can drive the car without worry and we'll help you work through the problems."

Thoughts?

[oil pan 4]

First thing is charge the battery up now with an external charger, don't wait till later.

[BabyDiesel]

I don't have access to a battery charger tonight. I just went out to check the battery voltage and it has come back up to 11.4

[BabyDiesel]

Edit - The battery voltage was actually 8.5V when I got back home. I seriously have no idea how the car was running...

[BabyDiesel]

Update: Took the Insight for a drive to Wendy's, about a mile drive. Voltage had gone up to 13.5

Funny quirk about the car is that it charges with the IMA as soon as it is cranked, but stops after about 5 seconds

[Ecky]

Without an IMA bypass (as you described), the DC-DC converter won't run properly. My brother is actually having the same issue with his - he's getting an IMA light sometimes, and when it's on, his 12v sometimes starts to drain because the DC-DC shuts off.

Here's a good guide to make sure your DC-DC converter stays on:

Hybrid Automotive - Honda Insight (2000-2006) Battery Bypass Instructions

[roflwaffle]

The car will keep in running even with a nearly dead 12V (<6V?). As voltage drops, idle will slow, and once it's too low, different systems like the ABS will start to throw warning lights as they stop functioning. I'm not sure how low it'll go, but I've gotten to the point where my car was idling at ~300-400rpm and had a christmas tree of warning lights.

[Ecky]

I had my 12v battery die once, and the 12v dropped low enough that the hybrid system shut off, which shut off the DC-DC converter. The engine still ran even when the voltage was so low that the instrument cluster shut off. It didn't run well, but I was able to drive it across town and get home.

[BabyDiesel]

Ecky, that tutorial is exactly what I needed! I'm going to bypass the IMA tomorrow during my lunch hour. It looks simple enough.

Yep, my dashboard lit up during the last few miles. Then started going out during the last half mile home. I was scared that it was going to be undriveable for work tomorrow. It's good to know I had a little more breathing room though, thank you roflwaffle and Ecky

I'll post about the procedure tomorrow after it gets completed

[Natalya]

Mod to keep 12 volt battery charged - Insight Central: Honda Insight Forum