DIY disaster - Need Help!

Hi everyone,

Multi-year lurker and beneficiary, but first time poster. I have done a lot of DIY projects on my 2005, and yesterday I did two, which has led me to a major problem. First, what I did:

I read a thread regarding cleaning of the HV battery fan. First I disconnected the auxillery battery, and then I took apart the back seat area casing, carpeting, etc, disconnected the two plugs for the blower, and cleaned it with an air compressor. BTW - I have 98,000 on this car and there was only a light coating of dust - don't waste your time . Like an idiot, I moved on to the next job without testing for a restart.

Next job was the auto-leveling headlight issue. I took out the sensor and opened it, only to find sludge instead of springs. After a lot of cleaning, I got the terminals relatively clean and replaced the 'springs' with ball-point pen springs. I noticed major corrosion inside the piece, and two small corroded leads on the cover piece actually broke off. I re-attached and connected the sensor.

Now, the Prius will drive with the HV battery, but the ICE won't start! I read codes P0000 and U0100 with the scanguage II, and as others have mentioned, the gas level blinks at 1 pip and then all pips. The red triangle appears with the car/exclamation point on the MFD, and strangely, the temperature outside reads as "E." My coolant temp reads at 31 degrees F.

The aux battery needs to be replaced (11.4v at rest), and I thought that disconnecting it may have been the last straw. However, I also tried to jump the Prius with my Rav4 this morning with no luck (scanguage read 13.8v on the Prius while connected to the running Rav4.)

I have checked all the clip-in connections I made while cleaning the blower fan, the headlight sensor, and the aux battery. At this point my only guess is that the headlight sensor is causing the problem, though that seems ridiculous because a. It was already non-functional, and b. It's an exposed part and could be damaged while driving; would seem like a major design flaw, and some Prius don't even have it.

Gas is actually at about 4 pips and SOC is roughly 55.0. All dealerships are closed today, so I'd have to wait. Please help if you think you have anything useful - I'm hoping Patrick will take a stab at this !

Frustrated and anxious,

Dave

 

1. Traction battery fan: recheck any wiring harness connectors that you had removed. Make sure that the plastic locks have engaged.

done.


2. 12V battery: Disconnect the negative battery terminal cable at the body for a few minutes so that the logged DTC has a chance to clear. While waiting, check the tightness of the positive terminal cable connector at the battery. Then reconnect the negative terminal cable and make sure it is tight, both at the battery and at the body. Try to make the car READY.

I did so, and the same situation occurred, plus the following: The MFD briefly gave a message like "The transmission lock position is abnormal..." but the entire screen went blank after about 1.5 seconds. I then tried to shut the car down by pressing START again, and everything fired up (with the same problems as before.) I wish I had a chance to read that message, but will try again and see if I can get it to replicate. Don't want to work for too long though and deplete the traction battery

 

Tried as you suggested and removed the terminals from the prius battery. Hooked up directly to the Rav4 (with + to + and -Rav4 to frame on the Prius. Ran the Rav4 at 2000rpm for a minute, and cabin bulbs, etc are on in Prius. Went to start, and exact same sequence comes up. Strangely, does not seem to be the battery then. Also, there are only 2 hookups on the HV fan, very simple and obvious; those are snapped in. I checked around for other areas or connections I may have knocked loose, but found none. It seems the only thing would be the headlight sensor... but why would it's malfunction impair the starting of the ICE? Does it carry other information as well, and maybe I broke a circuit? Has anyone run a Gen II with that sensor totally removed?

I'm baffled.

 

Ken - there is enough space to get your hands in to take out nuts, etc. Maybe you could smuggle a beer bottle in there but its not very roomy. What are your thoughts on the jumping procedure where I bypassed the 12v battery and went to another running vehicle?

 

Thanks for the ideas, guys. I also thought about that switch, but its on the opposite side of where the fan is, and it looks fine and secure. Additionally, the car can drive using the HV battery, so I would assume that's double confirmation its connected. Will get a tow to dealer today and update when I found out. My guess is that the low 12v battery may have given an error message into the hybrid system that needs to be cleared and that I can't with just a scanguage. I simply didn't do anything complicated, nor did I drive around the car in this state, so I just can't imagine the problem being severe. At least I hope!

 

Thanks 2009 - I removed the assembly completely so dust was only being blown onto my driveway

Patrick - agreed; its a strange thing. I don't know if it matters, but originally, I disconnected the positive connectors to the 12v battery, not the negative cable (this seemed quicker). Though, as you said, everything should have cleared after a minute with no 12v power, and should have been ready to go when connected to my 12v Rav4 source. One more thing - you mentioned "An error code logged by the skid control." I find it unlikely, but after doing the work, I went to move the Prius and forgot to disengage the parking brake; I noticed the VSC light come on.... again, I doubt this as well.

Oh well, flatbed just left and hopefully I'll hear something from the dealership in a few hours.

 

By positive terminal I meant the plastic snaps, and I agree the whole connection could be dangerous (it also would be a lot more hastle I think).

*UPDATE* Got a call from the dealer - they said nothing major seems to be broken/damaged, etc, and that they would probably need a few hours to clear codes and do diagnostic tests. The hybrid specialist speculated that a short my have blown a fuse, or something of that nature. Got the impression they figured it to be something of a minimal nature (I realize typing this subjects me to the possibility of Murphy's Law) Will update again when I hear more details.

 

Just got back from dealer, and the culprit was a blown 15A fuse (coded as 3091 C. Interestingly, this also cured a small problem I was having. About a month ago, my auto driver side window would go full up and then lower to half height consistently, no matter how far it lifted initially (as long as it was on 'auto up.') This no longer occurs...

I snuck by at only 181.31, much lower than my fears, though much greater than a $1 fuse costs. Wish I knew more; this has been a strange series of events.