Hey all, I have code p0a94 and looking at my inverter reservoir coolant is green and I'm not sure why. Is there a similar coolant but with green, should I change it? Is there anything else simple I can look into to try to do for this code?
welcome! yes, most commercially available coolant is green. or was, back in the day. so someone used a non toyota coolant, which may or may not be okay. when i opened the radiator of my first toyota, couldn't believe the color. had it flushed and refilled, only to find that it was pink again. expensive lesson learned.
What is the repair history of this car? Did DTC P0A94 just appear out of nowhere or did you buy the car with that fault existing? The coolant is supposed to be pink, which is the color of Toyota Super Long Life Coolant. Inexpensive coolants are sometimes colored green. P0A94 means the inverter has a serious problem with the high voltage DC/DC converter. The problem was not caused by the improper coolant. If you wish to DIY you will need Mini VCI to read the three-digit info code which is posted along with P0A94. That will help to determine whether the root cause is with the inverter, HV ECU, or transaxle.
Thanks for quick reply Bisco & Patrick. I had the triangle warning on and wouldn't go to drive or reverse a couple weeks back. Toyota charged me $560 to tell me that 12v battery, main relay #3 and maybe the main battery needed replacement. Cost $4500 plus. Looked up some info and cleaned main battery and recharged 12v battery. Worked for couple weeks, and stopped with p0a94. Anyway just finished replacing the main relay #3 and took it for a few miles. All is working for now. Not sure how long it will last. Do you think main relay can cause this code?
If by "main relay #3" you mean one of the relays that switch high voltage in the traction battery enclosure, that certainly could cause a problem with the inverter's proper functioning, and therefore cause P0A94. What is the odometer reading on this car?
Yes, high votage relay. 151k miles. Checked all the cells all around 7.8volt and all less than 0.2 Volt delta. Cleaned all the connectors and bults, applied die electric grease.
Hi all, 2 days later, my car stopped again with the triangle warning sign. I had the HV battery exposed so I unplugged the interlock and plugged it back in, was able to drive home, but warning sign is on. Is this the correct mini vci? Do I need anything else in order to scan for code? MINI VCI FOR TOYOTA Mongoose OBD2 USB Interface A++ V10.10.018 Toyota scanner Condition: New $15.99
an old laptop with the correct operating system, that you won't need for anything else, there may be virus.
Hi All, Finally was able to do a health check and no problem as of 10 days ago. Got the warning again and first I got the following codes: p0a0d, p0adf, c1259, c1310, b1421, c2318. Needed to jump the car. After jumping got these codes: p0adf, b1421, c2318. Here are some pics of diagnostics, not sure what to do next. Any ideas?
The important DTC are the ones starting with "P". P0A0D means a problem with the orange high voltage traction battery interlock switch. This is located on the left side of the traction battery case. Check the switch to make sure it is properly installed. When inserted, you pivot the lever 90 degrees, then slide the lever down to lock. P0ADF means a problem with the system main relay wiring which switches the negative side of the traction battery. That wiring may be shorted to ground. Perhaps this relates to the relay that you earlier replaced? You need to subscribe to techinfo.toyota.com if you wish to knowledgeably address the second problem. You also need to either fully-charge the 12V battery, or replace it.
Thanks Patrick, I will look into subscribing to techinfo. I disconnected the auxiliary battery and the only code remaining after about 10 minutes of driving was b1421 and no warning sign. Just want to make sure the HV battery is not the issue.
