Just as with any other vehicle, sometimes your truck needs a jumpstart. Some trucks have 2 batteries and figuring out how to do it properly can be confusing. Here’s how to jumpstart a pickup truck with two batteries.
To jumpstart a pickup with two batteries, pop the hood, locate the batteries and attach the jumper cable to either of the 2 batteries in the vehicle that is dead. Attach the other side of the jumper cables to the battery in the vehicle that is not dead, then start the engine and run for 10 to 15 minutes. Now try starting the dead truck.
Jumping a pickup with two batteries isn’t too difficult, but you must do everything properly to avoid the risk of hurting yourself or damaging the vehicle.
When Do You Need to Jumpstart a Truck?
You’ll likely need to jumpstart the dead battery of a diesel truck when your battery is nearing the end of its lifespan or if you accidentally left the interior lights on all night. If you’re noticing the following signs, it’s better to have your battery replaced rather than worry about being stranded with a dead battery:
- Need jumpstarts often
- Voltage meter on the dash shows low voltage
- Lots of corrosion visible on the battery posts
- Battery shows signs of leakage
If you’re suddenly hit with a dead battery, then it’s important to know how to jumpstart your truck. Some trucks are diesel, but you should know the fuel type your vehicle takes before you begin—the process works differently with gas-powered vehicles.
For best results, you’ll want to phone a friend or use a second truck if you have one to jumpstart your diesel truck. To access the batteries, pull the lever or push the corresponding button to pop the hood on the vehicle.
Release the safety lock and open up the hood. After you open the hood, ensure it stays open by using the prop on the inside of your hood. Some vehicles have a spring-loaded hood that can stay in place without additional support.
Most batteries are located in the hood, but in some vehicles, it can be found in the trunk to help with weight distribution. If in doubt, check your owner’s manual, and you should be able to find where your battery is located in your truck.
Once you’ve located the battery and got the hood open, move the vehicle you’re planning to jump from into position to make the process easier. Both vehicles should be in park, or neutral for manual transmissions. Make sure your lights and any other accessories in your car that use electrical functions are turned off and have been off for 10-15 minutes.
Ideally, the donor vehicle’s battery should have enough voltage to handle a transfer. A multimeter will do the trick to test the battery’s charge if you have one on hand in your truck. Between 13.7 and 14.7 volts is ideal for a running engine, and 12.6 volts is optimal when the vehicle is off. If the vehicle reads down to 12 volts while running, it’s only operating at 25% efficiency.
If your donor truck has low voltage, you run the risk of not only failing to charge the dead battery vehicle, but also ruining the donor trucks’ battery as well.
Jumpstarting Your Truck
Ensure that the vehicle being used for the jump is not switched on. It’s dangerous to work around car batteries when the vehicle is on. Next, you’ll need to discern which battery on the disabled diesel truck has thicker cables. This is the battery you want to jump. If both cables seem to be the same size, you can jump either battery.
You will need some jumper cables. It is a good idea to always have a set in your truck in case you need it or you can help someone in need of a jump.
Connect the red clamp cable to the positive terminal lug of the dead battery vehicle and subsequently to the charged vehicle. Repeat this process with the negative cable. The negative cable can also be attached to any metal and unpainted part of the vehicle.
Once connected, start the truck you’re jumping from (the one with the working battery) and then the vehicle with the dead battery.
Let the vehicle charge for 10-15 minutes so that your battery will be good to go. After that, you can turn off the truck you’re jumping from but leave the affected vehicle to charge for a while longer.
Two-Battery Pickup Trucks
If you’re seeing a battery warning light, and you’re not sure which one needs charging, you can use a multimeter to check each of the batteries. If only one of them is dead, you can follow the above steps to jumpstart that battery to get some charge back. If you need to charge both batteries, you can charge both at the same time in parallel or series.
For parallel, identify the positive and negative terminals, usually denoted with a (+) for positive and (-) for negative, and connect one end of the jumper cable to the positive terminal on the dead battery and then the other end of the cable to an unpainted metal surface on the working battery.
Essentially, you’re joining both of the positive terminals and negative terminals together.
To jumpstart in series, connect the positive terminal of one batter to the negative terminal of another. If in doubt, refer to this guide on charging batteries in series or parallel.
Once your battery is fully charged, you should leave your truck to sit for 15-30 minutes to respond to the charge. Attempting to use the truck before it’s settled properly can result in electrical components malfunctioning and causing other issues in your vehicle.
Once your truck’s back up and running, you should ideally take it to a mechanic shop to have the battery replaced. A dead battery is a liability in your truck, and you’ll want to have it addressed quickly.
Jumpstarting a pickup truck with two engines can be fairly straightforward as long as you follow some simple safety precautions.
Make sure that you’re hooking up the jumper cables correctly and that you only start up the cars when everything is wired, and you’re ready to do the transfer. Hopefully, with your pickup running again, you’ll be back on the road in no time.
Valik loves tinkering in the garage and is currently restoring a 2000 GMC Sierra 1500 truck. He also writes about the progress on this blog. When not in the garage, Valik is also a web developer and a blogger. I know, strange, a hand in two completely different worlds. And that is the way he likes to keep it.