New member looking at several Sparks all throwing codes

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New member
May 16, 2024
Columbia, Maryland
Hi Spark EV experts,
I'm new to the forum and had one Spark since new for 7-1/2 years, had to let it go after getting the warranty run-around. Despite that I miss it and now looking to buy another one. There is a candidate available locally, 2015 with 37500 miles but throwing the below codes from my OBD2 scan tool. Haven't been able to find full background on these. The car has an older 12V AGM battery, the SVS light is not currently lit, and I've noticed threads stating that replacing the 12V AGM battery addressed some codes.

P0B0D Auxiliary Transmission Fluid Pump Motor Control Module
P0AC4 Hybrid Powertrain Control Module Requested MIL Illumination

Any advice regarding these codes would be greatly appreciated. Thank you!
Update - after I posted someone on one of the forums bought this particular car despite these codes. Is there a codes-specific thread on this site? I haven't found one dedicated to trouble codes or gds2, but maybe I've missed it/them. Still curious what codes might be tolerable, and which ones might point to larger problems. Thank you!
Yeah most of the time replacing or charging fully the 12V AGM addresses many issues because all the powertrain computers run on 12V and throw fault codes if automotive voltage is unstable or drops below a certain threshold.

My Spark EV threw a cautionary P150D P150E and P0AC4 in 2022 which ended up being a loose negative battery post clamp causing intermittent connection issues. Cleaning the post up with a steel wire brush then tightening the clamp and clearing the code kept them cleared with no issues.

In another instance, I threw powertrain codes that included the codes above plus a tachometer error because I engaged the parking brake while moving at 1 km/h on a dirt road. The rear tires locked while the front tires continued a few position ticks forward which triggered a panic attack inside the PCM. You'd think this would be more gracefully handled because it's related to traction control, but no.

In both these instances, the car was still drivable without any loss in performance. I still cleared the codes before going on highways, but sometimes it can just be very transitory or intermittent errors/faults that are easily resolvable.

I don't have an active service manual subscription right now, but for $15 you can get every conceivable bit of detail about this car including the specific trouble codes for a month for any particular make and model year car with AllDataDIY. If you subscribe to the newsletter they give seasonal 10-15% discounts.

EV and ICE computers are also susceptible to EM interference, galactic cosmic rays, and geomagnetic storms from our Sun's space weather (flares, coronal mass ejections, prominence eruptions, etc). Memory can sometimes have bits flipped which corrupts firmware or induces voltages in signals, triggering faults. In these cases, modules can be fixed by being reprogrammed or replaced. De-energizing the entire vehicle for 10 minutes can reset volatile memory and fix many issues.

When you see a Spark for sale with codes, it's important to look around and visually inspect the car for identifiable body damage from a collision. If the forces are strong enough, a Spark EV involved in a front or corner collision stresses connectors and wire harnesses, damaging them and their connections in unintuitive places (or ripped away / crushed in the impact area). Sometimes damage is invisible and gets missed by dealership techs.

You can also learn a lot by continuing a test drive. You can take note of how the drive feels if power is limited, unusual noises, and so on. There's always the possibility that the error code was a one-off.