Prius Gen 1 Issue (2003)

I have been watching videos and I note that there are two leads that come off the battery unit. Is one of the recommendations to simply pull the main fuse and then just clean those two leads? Looks like they are pretty easier to get to.

All the voltages at least look good I think?

 

Can I remove the battery cover without removing the battery from the car? It does not look too crazy to remove except for weight but looking at options.

When I wrote "Main Fuse," I meant "Orange Safety Plug." I think some videos called it a fuse.

 

I could get a used Battery Control Module for $62 with S&H. Not expensive as car repairs go and ready to go if I cannot clean the contacts.
Is the module inside the cover or outside the cover? It looks inside from the videos but cannot be 100% sure.

Also, if I clean the contacts on the battery itself, would it be easier to remove the battery from the car?

 

Need to see what codes you may get to start, either with a code reader, go to the dealer, or using tech stream.

 

I just got done. Decided to just simply replace the module instead of cleaning it even though I saw corrosion.
I did clean all of the plates on the battery and all of the bolts on the batteries themselves however.
Immediately throws up the exact same codes when I start the car. Does still start and shows good battery voltages on all the cells.

Any other suggestions? Would simply replacing the battery (I know expensive) solve the problem?

Found a battery listing which has battery with 2nd gen cells and the battery control module already installed.

 

Reading through that, I had disconnected the Hybrid battery and 12 v battery before cleaning the cells and replacing the battery control module. That should clear all codes.

Never put it in neutral or drive. I think that might at least eliminate the transmission based on what I read. I did not clear the 3009 but did clear the 3000 code and the P3000 came back instantly and I believe it was whether the engine was running or not. I would not think the inverter would be running when the engine is not running.

It is possible I messed up something of course when I cleaned the battery and replaced the battery control module though. I don't think so but need to consider everything. Could also be that the module does not work, whether listed as working or not.

I put two inverters on my eBay watch list however just in case.

 

It was based on my interpretation of the link Ammdb provided.

It was nighttime when I read their response so did not do any experiments at the time

According to this however from the link
The first step is to clear the P3009 trouble code and then turn the key or push button to key on/not ready mode, (This is IG ON on a Gen I or the second position on the ignition switch (after ACC)) wait 30 seconds and if the code comes back, the leak is in the battery case. If the code does not set, turn key or push button to "ready mode"(start on the Gen I) and immediately shift to neutral and stay this mode for 30 seconds. If the code returns, the leak is in the power cables or inverter. If the code did not set, shift to drive and if the code resets now, the leak is in the transaxle. This is something that can be done in about minutes with a scan tool while never removing any components and not leaving the driver seat.

That is what I did. Key is the on position, gas engine off, and code comes back within less than 30 seconds. Unless what is written here is not accurate, at least right now the battery seems to be a problem.

 

I took the code description of 3000 Battery Control System as being what it listed.
I also took the code description of 3009 Leak Detected at being what it listed.
When my 2001 Mustang threw a fuel pump code or O2 sensor code, I assumed that is what they meant.
It is fine in a way because you do the best you can with the information you have at hand.
Before I got a response I had already ordered a replacement battery.
If I end up replacing the inverter too, unfortunately mistakes are made.

My concern is that my roommate states that before cleaning the battery and replacing the battery module that the codes did not pop up as quickly as they do now. They took a few moments. I am wondering if either the replacement battery control module is bad or if I damage something when cleaning contacts or cleaning the connection between the battery and the control module.

Gloucester Toyota of Gloucester Virginia. It is a fairly small town shop with not that many hybrids. They did replace the inverter coolant pump last year in my 2009 Prius though. Of course any decent reader will give you the code for that and not obscure and need techstream.