Gen 3 Prius Care, Maintenance & Troubleshooting Whether you've got a brand spankin' new or an aging 2010, 2011, 2012, 2013, 2014, & 2015 3rd Generation Prius, you can learn how to take care of your Prius. Wed, 11 Mar 2026 03:36:06 +0000 Wed, 11 Mar 2026 03:36:06 +0000 PriusChat https://priuschat.com/forum/gen-3-prius-care-maintenance-troubleshooting.97/ Head Gasket- what am I looking at? Wed, 11 Mar 2026 03:15:00 +0000 https://priuschat.com/threads/head-gasket-what-am-i-looking-at.259204/ https://priuschat.com/threads/head-gasket-what-am-i-looking-at.259204/ invalid@example.com (C Clay) C Clay Symptoms:
Used about 10 oz of coolant a week for about the last 2-3 weeks.
Just last week I started getting P300, 301, 302, and I think 304, but not until then. Of course I've had some hard starts- but minor. No over heating (I have a scanner app I use every time)
What is this? Normally I thought you would see a "steam-cleaned"...

Head Gasket- what am I looking at?]]> 9 Does my 2012 Cylinder #1 look OK? Tue, 10 Mar 2026 22:44:36 +0000 https://priuschat.com/threads/does-my-2012-cylinder-1-look-ok.259256/ https://priuschat.com/threads/does-my-2012-cylinder-1-look-ok.259256/ invalid@example.com (DavidinNevils) DavidinNevils
Does the cylinder look damaged or OK, please?

Thanks!]]> 33 Short-term storage Tue, 10 Mar 2026 15:47:35 +0000 https://priuschat.com/threads/short-term-storage.259267/ https://priuschat.com/threads/short-term-storage.259267/ invalid@example.com (Jayloc) Jayloc 6 Dreaded P0A80 Code - Car Running / Charging Good. Tue, 10 Mar 2026 01:30:38 +0000 https://priuschat.com/threads/dreaded-p0a80-code-car-running-charging-good.258775/ https://priuschat.com/threads/dreaded-p0a80-code-car-running-charging-good.258775/ invalid@example.com (PriuSocal) PriuSocal
I am new to reading HV battery readings and as mentioned above, bought an AP200 (recommended by another user to...

Dreaded P0A80 Code - Car Running / Charging Good.]]> 110 3rd Gen Reverse Polarity Disaster and 125A Fuse Access Mon, 09 Mar 2026 21:03:25 +0000 https://priuschat.com/threads/3rd-gen-reverse-polarity-disaster-and-125a-fuse-access.251715/ https://priuschat.com/threads/3rd-gen-reverse-polarity-disaster-and-125a-fuse-access.251715/ invalid@example.com (oskr24) oskr24
Hi guys. I won the stupid lottery by reverse connecting the 12V battery when I was inspecting it. My fault but some batteries could do with better labels. It was only a split second but I guess that's enough. Prius won't start. Some functions work such as the headlights. Some don't. I've spent many hours on the problem since then.

I found the 140A fuse inside the red clamp on the battery. It's fine.

I...

3rd Gen Reverse Polarity Disaster and 125A Fuse Access]]> 6 125 amp fuse replacement Mon, 09 Mar 2026 08:09:51 +0000 https://priuschat.com/threads/125-amp-fuse-replacement.237515/ https://priuschat.com/threads/125-amp-fuse-replacement.237515/ invalid@example.com (Chabelo) Chabelo (THis is the fuse that blows when reverse polarity is applied during a jump start).]]> 13 Battery has range, but doesnt work properly. Sun, 08 Mar 2026 17:37:26 +0000 https://priuschat.com/threads/battery-has-range-but-doesnt-work-properly.259217/ https://priuschat.com/threads/battery-has-range-but-doesnt-work-properly.259217/ invalid@example.com (Shimano Teryaki) Shimano Teryaki I own a 2010 Gen 3. I bought it last year, but i have experience with other Toyota hybrids, both newer and older and have never seen something like this, and i think neither did my local toyota dealership.

When i bought the car in october everything worked fine, just as intended. Got the consumption around 4 - 5 l/100km. At some point however on a random tuesday it started going crazy, it wasnt a gradual change, it just happened.

Getting to the problem since it started whenever i...

Battery has range, but doesnt work properly.]]> 24 Help TRANSMISSION CONTROL prius 3 Sun, 08 Mar 2026 16:27:17 +0000 https://priuschat.com/threads/help-transmission-control-prius-3.259232/ https://priuschat.com/threads/help-transmission-control-prius-3.259232/ invalid@example.com (Shacill123) Shacill123
C2303

C2304

C2305

C2306

I checked the wiring, replaced the sensor on the transmission, replaced the integration relay, and replaced the relay. The only thing left is the transmission control module. How do I replace it? If I just plug it in, the immobilizer light flashes.]]> 3 Changing brake fluid Sun, 08 Mar 2026 01:32:32 +0000 https://priuschat.com/threads/changing-brake-fluid.259202/ https://priuschat.com/threads/changing-brake-fluid.259202/ invalid@example.com (mhdriver) mhdriver 21 Engine Code P261B Water Pump Sat, 07 Mar 2026 10:47:07 +0000 https://priuschat.com/threads/engine-code-p261b-water-pump.259220/ https://priuschat.com/threads/engine-code-p261b-water-pump.259220/ invalid@example.com (Jon Batchelor) Jon Batchelor
From all I can read, the water pump in question is the smaller, less expensive silver/gray one for the engine, not the one for the inverter? Luckily, after watching videos regarding each, also seems to be the one that is easier to reach of the two.

I can get an...

Engine Code P261B Water Pump]]> 25 Front Brake Dusk Shield Sat, 07 Mar 2026 00:01:56 +0000 https://priuschat.com/threads/front-brake-dusk-shield.259207/ https://priuschat.com/threads/front-brake-dusk-shield.259207/ invalid@example.com (lindylex) lindylex
Thanks in advance.]]> 17 What would cause this brake pad wear, and any guesses about some unusual symptoms? Thu, 05 Mar 2026 04:59:39 +0000 https://priuschat.com/threads/what-would-cause-this-brake-pad-wear-and-any-guesses-about-some-unusual-symptoms.259208/ https://priuschat.com/threads/what-would-cause-this-brake-pad-wear-and-any-guesses-about-some-unusual-symptoms.259208/ invalid@example.com (MrPete) MrPete
Rear wheels now complete (rotors were at 7.8mm.)

Physical evidence of issues:
* Right rear outside pad has worn flat on the upper (close to rotor edge) side, several mm of differential wear (See photo.)
* All four rear caliper slider pins had sludgy black grease. They moved but not easily. (Redoing with the official Toyota grease made a night and day difference!)
* Rotating wheels definitely made a small...

What would cause this brake pad wear, and any guesses about some unusual symptoms?]]> 16 Ever worsening a/c problem Thu, 05 Mar 2026 02:56:07 +0000 https://priuschat.com/threads/ever-worsening-a-c-problem.255930/ https://priuschat.com/threads/ever-worsening-a-c-problem.255930/ invalid@example.com (Jon Batchelor) Jon Batchelor something detailed.

Started a few years...

Ever worsening a/c problem]]> 6 Prius Alignment Thu, 05 Mar 2026 00:10:01 +0000 https://priuschat.com/threads/prius-alignment.259231/ https://priuschat.com/threads/prius-alignment.259231/ invalid@example.com (gatorback) gatorback
[​IMG]


Google AI indicated that parts are needed to shim up the alignment.

I would like to have parts "at the ready" for the alignment. If anyone has experience with alignments, what parts does it make to have on-hand given the measurements in the screenshot?]]> 2 "EGR DELETE" Instructions Wed, 04 Mar 2026 15:26:32 +0000 https://priuschat.com/threads/egr-delete-instructions.241539/ https://priuschat.com/threads/egr-delete-instructions.241539/ invalid@example.com (Paladain55) Paladain55 Step 1: Pop the hood.
Step 2:...

"EGR DELETE" Instructions]]> 97 OEM 42450-47040 2010-15 HUB & BEARING ASSY, REAR AXLE, RH or LH Wed, 04 Mar 2026 14:14:33 +0000 https://priuschat.com/threads/oem-42450-47040-2010-15-hub-bearing-assy-rear-axle-rh-or-lh.259223/ https://priuschat.com/threads/oem-42450-47040-2010-15-hub-bearing-assy-rear-axle-rh-or-lh.259223/ invalid@example.com (gatorback) gatorback
1) What is the decision process / inputs to decide between OEM ($180- $440) vs aftermarket ($60 eBay/ AMZN)?

2) If buying OEM through eBay, what is the litmus test to verify it is truly OEM?

42450-47040 TOYOTA GENUINE PRUIS 2010-15 HUB & BEARING ASSY, REAR AXLE, RH or LH | eBay

3) If buying online from a Toyota...

OEM 42450-47040 2010-15 HUB & BEARING ASSY, REAR AXLE, RH or LH]]> 3 Quiet/COmfortable Tire Recommendations for 15" Wheels? Wed, 04 Mar 2026 03:38:32 +0000 https://priuschat.com/threads/quiet-comfortable-tire-recommendations-for-15-wheels.235749/ https://priuschat.com/threads/quiet-comfortable-tire-recommendations-for-15-wheels.235749/ invalid@example.com (SB6) SB6
I'm trying to figure out what tires to get with comfort/noise in mind. MPG is secondary. What are your thoughts? These are the tires I've seen recommended in my research so far:
  • Bridgestone Ecopia EP422 Plus 91H
  • Michelin Defender T + H 91H
  • Continental TrueContact Tour (91H or 91T?)
  • Hankook Kinergy PT H737 91H
  • General Tire AltiMAX RT43 91H
  • Yokohama Avid Ascend LX...

Quiet/COmfortable Tire Recommendations for 15" Wheels?]]> 17 ABS Actuator not so infamous C1345 Tue, 03 Mar 2026 19:11:51 +0000 https://priuschat.com/threads/abs-actuator-not-so-infamous-c1345.259219/ https://priuschat.com/threads/abs-actuator-not-so-infamous-c1345.259219/ invalid@example.com (QLMS) QLMS
Symptoms: intermittent regenerative, breaking and skidding because of the ABS system malfunctioning. Happened after a hard braking, but for months leading up to this I could hear the break accumulator cycling way more than it was supposed to. Before and after the hard braking (to avoid an accident) I could hear a hissing sound under the dashboard. This became worse after slamming on...

ABS Actuator not so infamous C1345]]> Rain Water Leak in Trunk Tue, 03 Mar 2026 02:59:52 +0000 https://priuschat.com/threads/rain-water-leak-in-trunk.150422/ https://priuschat.com/threads/rain-water-leak-in-trunk.150422/ invalid@example.com (c64rbr) c64rbr
Rain Water Leak in Trunk]]> 20 Uneven rotor wear Mon, 02 Mar 2026 14:31:37 +0000 https://priuschat.com/threads/uneven-rotor-wear.259147/ https://priuschat.com/threads/uneven-rotor-wear.259147/ invalid@example.com (Noahdoge) Noahdoge
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