Master Warning Light, P3030, P3000, P3005 & P3006

About a year ago, I had the Master Warning Light came on as reported in this thread:

http://priuschat.com/forums/international-owners/6539-prius-in-singapore-16.html#post1059830

I repaired the problem by cutting some wires and connecting the sense wires directly to the PCB, no components were replaced.

The same MWL came back on 13th Mar about 18,500 km later. This time I have the SGII and able to use the SCAN function to read the stored codes, P3005 & P3006. Another code P3030 was retrieved using the FRZD freeze data function at PID02. Using the CMND function, I can manually read all 3 codes from Bty ECU and P3000 from HV ECU. 3 INF codes were ic1=389, ic2=125 & ic3=123. I tried to clear the codes only to find P3030 returned immediately and system was not able to get into [READY].

As suspected, the KOH was leaking again.



This time, the Bty ECU PCB was burnt and beyond repair. My local dealer do not have stock I found a re-manufactured part on eBay for USD123.50 and shipping USD60.75 from US.

While waiting for the part, I removed the whole HV Bty assembly for cleaning.



The copper plates were removed from the Busbar and soaked in vinegar. I used wire brush to clean it.



The previous silicone reseal did not work. This time I tried 3M Scotchkote as below:



Be careful to leave about 1 mm gap from the left and right edges. Use a Voltmeter to measure both the terminals w.r.t bottom screw holes to make sure they are zero volts.



Some of the modules have some voltages when they were assembled together as below. They have zero volts when I took them apart.



I have no choice but to redo some of them to make sure there are gaps in between.

I also had to add in both the left & right resin plate by cutting them from some thin piece of plastic.



Previously, I have recorded my Bty pack block voltages & resistance in this thread:

http://priuschat.com/forums/generat...ttery-frankenstein-project-4.html#post1206003

I tried to re-arrange the modules so that the high & low resistance modules and high & low voltages are combined to try to balance out.

The part finally arrived on 1st Apr. After assembling back, all the warning lights were gone now. I took it for a spin and so far so good.

I measured the new block voltages & resistance:

	Column 1	Column 2	Column 3
0	Block	New Resistance	New Voltage
1	1	20	15.55
2	2	20	15.48
3	3	21	15.45
4	4	21	15.49
5	5	20	15.5
6	6	20	15.54
7	7	21	15.46
8	8	20	15.48
9	9	20	15.5
10	10	20	15.5
11	11	21	15.52
12	12	22	15.47
13	13	20	15.51
14	14	21	15.5
15	15	20	15.51
16	16	20	15.5
17	17	20	15.44
18	18	21	15.48
19	19	20	15.49

It seems like the voltages are as uneven as before but the total resistance has been reduced from 398 mΩ to 388 mΩ.

 

Nope, since the highest and lowest voltage were 7.64V & 7.58V respectively, I did not think the difference of 0.06V was that significant.My only concern is to prevent or at least delay the leakage.

IMHO, the better solution is to replace with Gen 2 or 3 modules that have metal casing but the cost will go up tremendously. Besides, I may decide to scrap it before it reach 10 years (20 months left).

 

Yes, replacement parts are difficult to get since our local dealer sold not more than 20 units and it is already more than 9 years since they started selling. I don't expect them to keep spare parts for old models. That is not a problem to me as I can still buy from online. My biggest disappointment is that they did not do a good job on SSC-40G.

 

OK, I also recorded the DTC with TS Lite. The INF codes were exactly the same except the numberings.

So, it is really possible for SGII to read INF codes.