So I know it’s possible because I just did it today, my friend called me asking if I could come jump her car and I did, using the starter battery in the hatch. She has a Mercedes SUV and it ended up working. I was wondering if there are any risks to the health of the car or car battery by jumping someone else’s car? I know the battery is not as strong as a standard vehicle, and while I was happy to help her out I don’t want to keep jumping people’s cars if it’s going to possibly hurt my battery. I didn’t research it before trying, but afterwards I searched some and got a lot of conflicting answers. So I was hoping I could get some help here. Thank you!
Officially, the manual says no, you should not jump start another vehicle. Might be more worth it to carry a battery jumper (those rechargeable Li-Ion battery packs).
Can it be done? Yes. Should it be done? As Tideland mentioned, the Owners Manual says No. Back when I joined this forum, there were plenty of cases of very expensive electronics repairs caused by improper jump starts. Most of them were trying to jump start the Prius, not use it to jump start anything else. Since then, some of these damaged Prii have been found to have just a blown very-major under-hood fuse, nothing else. Though not all of them. Due to those stories of very expensive repairs, I have consistently refused to give jump starts with my Prius. Use a separate jump pack instead. I'd even rather pay for someone else's emergency service call out of my own pocket than risk giving a jump start. Yes, the repair cost of those jump accidents were that high. Some people who really know what they are doing have given numerous jump starts without damage, but this demands more car expertise than jumpstarts with 'ordinary' cars. I also believe that jumpstarting another Prius is significantly less risky than jumpstarting any vehicle with a larger engine and big starter, such as a pickup truck or SUV. The Prius 12V system is designed only to boot up some computers and run the brake booster, not to crank any traditional engine starter.
Answer is no, but if you absolutely must assist another vehicle, this is the safe way to prevent any damage to your sensitive electrical elements in the Prius. Make your Prius Ready, connect jumper cables in the normal, safe sequence. DO NOT ATTEMPT TO START THE VEHICLE WITH THE WEAK/DEAD BATTERY! Instead, allow the Prius to cycle the engine on, then rev the engine and allow it to charge the hybrid battery and the other vehicle's battery. Allow about 15 to 20 minutes for this charging process. Before attempting to start the other vehicle, disconnect the jumper cables. This will prevent any surges of power to and from the other vehicle and your Prius when the large energy drain from the starter motor in the other vehicle engages. Hopefully, the other vehicle's battery was in an acceptable condition to accept the charge from the Prius and successfully start up. The only way I'd attempt to jump start another vehicle from the Prius while still connected to the other vehicle, is if I disconnect the ground cable of the Prius battery and the Prius' body first. That way, the sensitive electronics of the Prius would be isolated from any surges from the operation. Posted via the PriusChat mobile app.
Only way I'd do it is to disconnect the 12v in the Prius and hook the cables up to the dead car. It's a tiny battery so it's only good for a little boost, not really gonna charge or crank a really dead car. I wouldn't have the 12v connected because it's not worth risking frying anything in the Prius with the voltage spikes in my mind.
Invest in a charger, and jump pack. You can get both for under $100. A lot safer than risking your Prius. A lot easier and quicker too!
Lol, she’s a friend from class and actually called me asking if I had jumper cables. Just friends though It seems I got lucky and the general consensus is I should not in the future. Good to know. It sounds like it’s mostly safe to trickle charge, disconnect the cables and then start the dead car though? Assuming there isn’t a massive short in the dead cars electrical system. I know my dad has a jumper box but it sounds like I ought to get one for myself to carry around.
Yeah with a Prius that's the best policy. That way you're never risking more than what you spent on the battery pod.
A lot of steps involved in disconneting a Prius battery. Remove "junk" in the trunk. Remove cover carpet, if you have it, remove spare tire cover, remove plastic tray, usually with junk in it, remove battery cover, disconnect battery. A jump pack is easier!
And totally UNnecessary.......if you use a little common sense. You should not try to jump a totally DEAD vehicle; it should at least have enough life to light the dome light. And you should NOT have the Prius in READY or ACC mode. It should be completely OFF.
"They" also say never to tow anything, I'd have no qualms about doing it, at aleast to a passenger car sized battery, I can't see a way it could hurt anything at all.
User owner manuals are just another man’s opinion or suggestion. Never underestimate the power of a 12v 40amp battery!!!
You need to think this through a bit more. People are STUPID. They can make all kinds of mistakes. Those mistakes can create a much BIGGER disaster for vehicles with a lot of electronic controls.
If wasn’t for those people and dashcams, YouTube wouldn’t have hours of entertaining videos of under severely power vehicles towing going out of control and smashing into innocent bystanders and vehicles. By the way, did priuschat ban you for a while? Haven’t seen ya lately here.
No, I banned me for a while. I am trying VERY hard not to participate is useless conversations. But it is a tough task.
