Jump-Starting A Hybrid Can Be Risky. Here's The Right Way To Do It

Picture this. You're ready to drive around town in your hybrid car and realize you left the headlights on — oops. This could mean a couple of things, but there's a pretty good chance that the battery is dead. Or maybe it's a different scenario. Perhaps you left the car on standby while listening to the radio, or recently bought an aftermarket accessory known for parasitic draw. Regardless, it can be a real pain when you need to jump-start a car. 

Can you even jump-start a hybrid safely? The simple answer is "yes". And yes, it is possible to jump-start another vehicle with a hybrid, but it's strongly recommend that you don't do that. Hybrid cars aren't made with jump-starting other vehicles in mind, which means they're not made to handle that kind of power transfer. 

Now, most drivers know how to jump-start a traditional vehicle, but brain farts happen to us all. What if you mix up the terminals or the jumper cables? It can be problematic if you try to jump-start a hybrid the wrong way. A few things can happen: a damaged battery, harm to the vehicle overall, and some fried electrical components and/or wiring. Just like a traditional car, a hybrid will suffer from an improperly performed jump. More so, because hybrids draw power from a battery and not just a gas engine. And it can be worse — even deadly — if you try to jump-start the hybrid battery pack. Never do that.

If you've jump-started a hybrid the wrong way, you may be second-guessing getting a plug-in hybrid, but let's not get ahead of ourselves. Plenty of Americans can't get enough of hybrid cars for a number of reasons. So, to keep it running, how do we jump-start a hybrid car correctly? We could say it's the same way we jump-start a traditional car, but it's not that simple. There are certain components to look for to avoid damage to the car and/or injury to yourself.

So, here's the thing. Just because this is a hybrid car doesn't mean it can run on the hybrid battery alone if it contains a charge. The battery isn't big enough; that's reserved for plug-in hybrid vehicles. Hybrids have a 12-volt auxiliary battery, found in all cars with an internal combustion engine as part of the powertrain. This is responsible for the ignition, HVAC system, safety systems, and other electronics. It's also the one we're using to jump-start this baby. 

Then there is the high-voltage battery pack, which powers the electric motor. This is the battery you want to avoid, and it's an important step in the process. If you mix up the cables and where to connect them, you're looking at costly repairs, blown fuses, and fried electronics. In some cases, this can lead to excessive heat from the power transfer and an explosion.

So, first things first. We should locate the 12-volt auxiliary battery. Every vehicle is different. Some hybrid vehicles have the 12-volt under the hood like always, or in the trunk, or even under the rear seat. As always, refer to your car owner's manual to help identify the model and where to find the right battery.

1. Find a vehicle with a good battery to transfer power from — a "donor car."
2. Park the hybrid on a flat, dry surface.
3. Turn off all electrical accessories and the ignition.
4. Locate the terminals for each car. The donor car should be powered by an internal combustion engine, so its 12-volt battery should be easy to find. As for the hybrid, most come with boosting or charging points in place of the terminals in the engine bay. However, if your 12-volt is also there, it'll usually kept safe under a fuse block cover.
5. Connect the jumper cables to the terminals of both cars. First the hybrid; red for positive (+), black (or unpainted) for negative.
6. If using booster cables, follow the same steps. Connect one end to the hybrid, then the other end to the donor car, connecting to the correct terminals with the engine off.
7. Make sure the clamps are attached and secure.
8. Start the donor vehicle, with slight pressure to the accelerator pedal for several minutes.
9. Then test the power transfer by revving the hybrid engine. If it's running, congratulations. Your car isn't dead.
10. Now you can safely remove the jumper cables attached to each vehicle, or booster cables if you used those. First the negative clamp from the hybrid, then the donor. Next, the positive clamp from the hybrid and then the donor.

If you happened to find this page after a failed jump, there's one small consolation. There are plenty of new hybrid cars under $35,000 to replace the old one.