Can't Jump Start 2011 Prius with Lithium Jump Starter

I recently had the experience of going to start my 2011 Prius and finding that it had absolutely no electrical power showing up on the dash board. Could not open any door electronically. Could not open the hatch. Had to open the driver door with the mechanical key.

I called the local Toyota dealership. They sent someone with a lead-acid battery jump starter. After a few tries we were able to get it to start. They then drove it back to the dealership where they eventually concluded that the 12V auxiliary battery was toast, even though it was less than 1 year old. They replaced it under warranty.

But I decided after that experience that I wanted to be a little more in control of the situation the next time so I bought a TackLife T8 jump starter at Amazon. This is one of those newer, Lithium battery powered jump starters that's small enough to carry around in your car all the time and can even be recharged from the cigarette lighter.

Problem is, I can't get it to work with the 2011 Prius. What I tried as a test was this..

- Disconnect the 12V cable from the auxiliary batter in the rear. This was to simulate the totally dead battery condition that I had encountered previously.
- Connect TackLife positive to the jump lug in the fuse box in the engine compartment.
- Connect the TackLife negative to the engine block. I had to use an old fashion jumper cable to reach the engine block. The TackLife cable alone was way too short. And nothing I tried that could be reached with the short negative cable would close the circuit. Nonetheless, connecting to the engine block with a helper cable did close the circuit.
- Press the Boost button on the TackLife. You need to do this because the TackLife looks for some level of battery voltage as a check that you've connected the cables with proper polarity. Not finding that, you need to press that button for the TackLife to apply voltage.
- Having pressed Boost the green light came on at the TackLife, indicating voltage power applied.
- Now in the driver seat I could see a flashing light indicting some life on the dashboard.
- I tried starting the hybrid system , both with Start button alone and with Start button plus break pedal depressed. The dashboard would light up completely, but I couldn't get the hybrid system to start or the ICE to come to life.
- The TackLife is designed so that Boost power only lasts 30 sec.s. After that time ran out, the TackLife turned off the power, and the dashboard went dead again.
- I tried this several times without ever being able to start the car.

So, all in all, I could not get the car to start with the Lithium jump starter. Has anyone done this successfully? Am I missing something basic?

 

Wow, thanks for the great comments folks! You're teaching me a lot.

- Disconnecting battery is not a good simulation of a failed battery condition.
I was wondering about that myself. Several people advice that the Prius hybrid system may need a 12 V battery present to start properly, even if mostly dead.

- Other jump starter like NOCO GB70.
That's interesting, I thought any jump starter should be able to handle a Prius, just because it shouldn't require much cranking current. But maybe the 30 sec. boost limit is a killer here and something like this NOCO would be better.

- Cables short because of thin gauge, lower cost wire. Look for bolts close to fuse box. Test circuit with multi-meter first.
These are good points. I tried would seemed like good connection points for black. Will have to look again with multi-meter in hand.

- Best to try out a new tool before a crisis.
Yes, my thoughts exactly. But if disconnecting the aux. 12 V battery isn't a good simulation then I'm not sure how to do it. Too bad I don't have the failed 12 V that the Toyota shop removed.

- Need to find out why the battery only lasted 1 year.
Yes, this makes sense. I questioned the service writer at the Toyota shop carefully on what the root cause might be. He had already lost my confidence when he didn't think to check the service record of my vehicle for history, given that it has never been serviced anywhere but in that one shop. But he told me that the technician had run the full suite of diagnostics and turned up no problem except the battery itself. Maybe I'm going to have to learn about this "parasitic draw test".

I wrote to the manufacturer of the jump starter, wondering if they might have tips for use with a Prius, like maybe a trick to make the boost interval last longer. They haven't responded yet, but probably won't at all. Chances are high this jump starter is going to get shipped back to Amazon.

 

In case anyone is interested, here’s a follow up.

I decided I would try once more to jump start my 2011 Prius using the TackLife T8 I had bought from Amazon. I expected it wouldn’t work any better than the first time and I’d soon be packing up the device for return.

Before starting, I followed one point made in this thread which was to probe around with a multi-meter for a good place to attach the negative clamp. It took a while, but eventually I did find a good place within reach of the short cable.

Then I went back to the same method as before, which was to simulate a dead aux. battery by disconnecting the positive cable in back. Several people in this thread pointed out that this might not be a good simulation. But I don’t have any other method available so I did the same thing the 2nd time around.

Having simulated the dead battery I pushed the Boost button on the TackLife, went to the driver’s seat, pressed the break and pressed the start button. Tried that twice without success. But on the 3rd try it worked! The “Ready” status showed up on the dash and, after 20 or 30 seconds, the ICE started. I repeated the procedure 2 more times and this time it worked each time on the first try.

I don’t really understand what was different the 2nd go around from the first. Could it really just be the way the jump starter neg. clamp was connected? The first time, it went through a long jumper cable to the engine block. This time it was connected with just the short cable, to a place close the positive jump lug in the fuse box. Hard to believe that would make a difference but I don’t have any other explanation.

So at this point, I’ve decided to keep the unit. I’m thinking that in a real emergency I should be able to finagle it well enough to get it to work.

By the way, the vendor did eventually respond to my e-mail support inquiry. They sent the manual which I already had, they repeated obvious points like making sure the unit was charged. I wrote back to them, before I had gotten the unit to work, saying that I thought the real problem was that the Boost interval only lasted for 30 sec.s and probably it needed 60 or 90 sec.s. I pointed out that a hybrid should not draw much current from a jump starter since the 12 V battery doesn’t do the real cranking. So the device could probably handle 60 or 90 sec.s of Boost on a Prius with no problem.

Of course they didn’t get it. The person at the other end probably wasn’t at all technical and was just working from a script. But what did surprise me was that they assumed the problem was not enough CCA so they offered to send me the next larger model, TackLife Pro, at no charge, and without requiring me to send back the unit I had. At this point I don’t need it but I was interested that the company was trying to be responsive.

One other thing is that this experience got me wondering how much current a Prius does require form the 12 V aux. battery to get the hybrid system started. I googled a bit and found this great article: irobin_org_prius_startup_startup.

The conclusion there is that it’s usually around 30 A peak but sometimes as high as 60 A. His overall conclusion was that around around 90 Amp-Seconds of juice is required.

Anyway, thanks again for the help provided in this thread!