Recently the Assist has been coming on way too easily. Any slight acceleration on level ground or the smallest barely noticeable incline will bring on 4-6 bars of Assist. With Assist on so often the SOC is typically in the 4-6 bar range as the car is too often in Assist mode draining the battery. No warning lights are coming on. This is a 2003 Insight with 12k miles on it and and a 20 month old battery pack that was replaced under warranty. The gas engine has plenty of power and is not an issue. I did drive the car very gently today for about 15 minutes using a steep down hill and gradual long way around up hill return and was able to get a full SOC less 1 bar, so the battery will still go to full charge. Outside temps are in the 35-45 degree range (Seattle). Any ideas as to what is going on here and how to get Assist to not come in so easily?
Have you also noticed a general decline in your MPG?
Anything done recently, like put on winter tires? Any service done? Perhaps they did you a "favor" and set your tires at 32PSI.
I also find that assist comes on too early in general though, especially at sea level. It was MUCH easier to avoid the use of assist when I lived in Santa Fe at 7,000' in elevation. It's almost impossible at sea level.
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To answer the questions in the replies, tire pressures were 38/38 front and 35/34 rear, but I have been running 43 front and 40 rear, so I added air to get back to those pressures. Mileage has not been affected and is typically the 52-58mpg range with a 54.8mpg lifetime. No work has been done to the car except an oil change with 0W-20 Mobil 1. The car is near sea level on an island in Puget Sound at elevations of 5-600ft nearly all of the time. Brakes are not dragging and this is a 5 spd car. When this behavior started about 3 months ago I noticed the significant increase in how often Assist kicked in and how little load caused Assist to kick in along with the rapid draining of the battery. Going up a hill that before would drain 4-5 bars from SOC now drains twice that. I did drive the car after adding air and there was no difference, Assist was still coming on too often. So what is going on here????
ive sometimes wondered if the bcm has programing that "tries" to balance the cells, or capacity(honda had to know this would be a issue). Ive had this happen here and there,but never could replicate the process.
It seems to me that it does. Recently, after a negative recal, the charging regime that followed appeared to take the battery near full with a fast charge and then trickle charge in two steps - reducing current down to about 1-2 amps, and then to about 0.3 to 0.6 amps. The end pack voltage was the same as what I've gotten from grid charging. I wrote more about it here: first grid charge initial results
Also, I recently read this idea and maybe it's something done in our cars. Often when the HV battery is charging, I see low current discharges at times:
"Interspersing discharge pulses between charge pulses is known to improve charge acceptance of nickel-based batteries. Commonly referred to as a “burp” or “reverseload” charge, this method assists in the recombination of gases generated during charge. The result is a cooler and more effective charge than with conventional DC chargers." Charging Nickel-Cadmium Batteries ? Battery University
that is very interesting! It follows the "random" pattern ive seen with mine. The only constant ive been able to reproduce is my old (#30) bcm doesnt do this vs the new one i have. (not to mention my mpg falls with the new bcm as well).
To the OP..Do you know what version bcm you have-or if it has been changed?
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