Nobody wants their car to suddenly stop working. Unfortunately, Toyota recalled around 75,000 of their 2004 Prius cars because of some technical issues that were causing them to stall. This could be caused by several different failures in the car’s system.
Not every single Prius will stall, but if you have a 2004 model, it may be a common occurrence. If you’re unable to get it started again, then you may need to have it towed. However, before calling the tow truck, try the methods we’ve outlined below in order to restart your Prius after it has stalled.
- Note: The 2004 Prius will often delay when you first accelerate, which may feel like the car is temporarily stalling. However, in this case the car is working fine, and you do not need to restart it or troubleshoot the system.
Method 1 of 4: Restarting your Prius
Occasionally, a Prius will just refuse to start normally. This is the result of some sort of power failure that is preventing the car’s computer from booting. If you find yourself unable to start your Prius, you may just need to reboot the computer, similar to when your computer freezes and you have to power it down and then restart it.
Step 1: Press and hold the “Start” button. Hold the Start button down with your index finger for at least 45 seconds.
Step 2: Restart the car. Start the car normally after the system has rebooted by pushing down on the brake and pressing the Start button again.
Tip: If you try to restart your Prius and the dashboard lights come on but they are dim and blinking, you may have a problem with your 12V battery. If this is the case, the battery may need to be replaced or jump started (see Method 2).
Method 2 of 4: Jump starting your Prius
If you’re trying to start your Prius and the lights on the dashboard come on, but they’re dim and flashing, you may be having trouble with your 12V battery. You will need to jump start it, if possible, and then have the battery checked at an autoparts store.
Step 1: Open the hood. To open the hood, pull the hood release lever. You should hear the it release and pop open.
Step 2: Connect the positive jumper cable to your battery. Connect the positive (red or orange) cable to the battery of the stalled Prius.
Leave the negative (black) cable clamped on a piece of metal or on the ground.
Step 3: Connect the second pair of jumper cables. Attach the other positive and negative cables to a car with a working battery.
Step 4: Charge the battery in the stalled car. Start the car with the working battery and let it run for about 5 minutes so that the stalled battery can recharge.
Step 5: Restart the Prius like normal. If the same thing happens, your car may need to be towed and have the battery replaced.
Method 3 of 4: Rebooting the warning lights
Another frequent occurrence with the 2004 Prius is that it will suddenly lose power while it is moving, and all of the warning lights on the dashboard will illuminate, including the Check Engine light. This is due to the system triggering a “fail-safe” mode that shuts off the gas engine.
Step 1: Pull off to the side of the road. If your Prius is in fail-safe mode, then the electric engine is still running and you’ll be able to pull over and park safely.
- Tip: Often, the keypad will be locked if it’s inserted into the dashboard holder. Do not force it out. You will be able to remove it after resolving the fail-safe mode.
Step 2: Press down on the brake and the Start button. Push down on the brake while pressing down on the Start button for at least 45 seconds. The warning lights will remain illuminated.
Step 3: Keep the brake pedal engaged. Let go of the Start button but do not take your foot off of the brake. Wait at least 10 seconds with the brake pedal still engaged.
Step 4: Release the brake and press the Start button again. Let go of the brake pedal and press the Start button again to fully shut off the vehicle. Remove the keypad.
Step 5: Restart the car. Try to start the car normally by using the brake and Start button. If the car does not restart, have it towed to the nearest dealer.
If the car does start, but the warning lights remain on, drive it home or to a dealer so that it can be checked for error codes.
Method 4 of 4: Addressing a hybrid synergy drive system that won’t start
Sometimes the Start button will engage the lights on the dashboard, but the hybrid synergy drive system will not start, so the driver is unable to shift into either drive or reverse. The synergy drive system connects the engine and gears through electrical signals. If these fail, you will need to follow the steps below to get your Prius back into gear.
Step 1: Engage the brake pedal and Start button. Step on the brake and press the Start button.
Step 2: Put the car in park. If you’re unable to put your car into gear, keep your foot on the brake and press the P button on the dashboard, which puts the car in park.
Step 3: Engage the Start button again. Press the Start button again and wait for the car to start.
Step 4: Attempt to put the car in gear. Shift the car into drive or reverse and continue driving.
If the above steps don’t work and you’re unable to engage the hybrid synergy drive system, call a tow truck to have the car taken to a repair shop.
If your Prius runs out of power while it’s driving and it doesn’t have any gas in the tank, the Prius will be unable to fire up the gas engine. It will try three times to engage the gas engine and then it will die immediately, which triggers a fault code. A technician will need to reset this fault code before the Prius will be able to be started again, even if you add gas to the gas tank.
- Note: A Prius may stall for other reasons than the ones mentioned above. For example, if any debris gets into the mass airflow filter, the car will stall or it won’t start at all.
For the 2004-2005 Prius models, the above methods are some common solutions to stalling. However, if you’re unsure about how to handle your vehicle stalling, you call always Ask a Mechanic to get quick, detailed advice from one of our certified technicians. If you’ve tried the above methods of restarting the car and they don’t seem to be working for you, be sure to have a professional mechanic, such as one from YourMechanic, inspect your Prius to determine why it is malfunctioning.
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