The short answer is yes, you definitely can. Although hybrids and plug-in hybrids are different from conventional ICE cars, there are some similarities, and that 12V battery is one of them.
This means that if your HEV or PHEV is unable to start because of a dead or discharged 12V battery (not the hybrid battery), then it is possible to jump-start the car with the same procedures as you would normally do on ICE cars.
There are, however, some tips that can help to make that process a smooth and worry-free transition. First and foremost, ALWAYS check your car’s owner’s manual before doing it.
In most cases, you will only have the services of a donor car with a healthy 12V battery and a set of jumper cables. With cars like the Honda City Hybrid or the Toyota Corolla Cross Hybrid, the steps are the same as conventional ICE cars.
Turn off EVERYTHING
Before the jump start procedure can be initiated, make sure that everything in your car (with the dead battery) and the donor’s car (with the healthy battery) is turned off.
Things like air-conditioning, lights, radio, GPS, seat-warmers, and other electronic features should be turned off. This is to avoid any possible surge of energy that may short circuit the electronics that were assigned to run these things in the vehicles during the jump-starting process.
Pop the hood & locate the battery
For cars with an exposed 12V battery, it’s pretty much straightforward, even in HEVs and PHEVs. Get the two cars as close as possible, and pop the front bonnet to gain access to both batteries.
Then, it’s just a matter of clamping the jumper cable on the positive (+) end of the dead battery, followed by the other red positive end on the donor’s positive terminal of the battery.
Next, use the black jumper cable and clamp the negative (-) terminal of the donor’s battery (the healthy one). For the other end, find an unpainted metal surface (like an engine mount bolt) within the engine bay of your car to ground the entire procedure.
Some cars may have batteries that are located in inaccessible places, but that shouldn’t stop the entire jump-start process. In this case, just look for the auxiliary battery terminal in your engine bay (usually a red rubber cover with a positive symbol, sometimes they’re black).
That’s your battery’s positive terminal, and the rest of the procedure is the same as an exposed 12V battery. In some cases like cars from the US, the 12V positive battery terminal can be found within the fuse box.
Ladies & gentlemen, start your engines
Once every clamp and cable is firmly secured (and the cables or connections are not touching each other), get into the donor’s car and start the engine. A few minutes and some revs should do the job to jump-start your hybrid vehicle back to life. Just get into your car after that and start her up.
Once successful, you may start removing the jumper cables. Keep in mind that the order should be the opposite of how you started the initial jump-start process.
The black negative clamp on the unpainted metal surface first, followed by the black negative clamp on the donor’s car, then the red positive clamp on the donor’s car, and finally, the red positive clamp on your car’s positive terminal.
Some warning lights may come on
In some cases, some warning system indicators may turn on after the whole jump-start process. For brands like Honda, you’re advised to drive a short distance at over 20km/h and it should do the trick and turn off the warning lights.
If it doesn’t, drive straight to the nearest authorised dealer or service centre to have the vehicle checked. All the best, good luck, and stay safe always!