Jump Starting: Simple but Dangerous
Jump starting a car looks easy in movies. You just connect the cables and go, right? Wrong. Modern cars are filled with sensitive computers (ECU, TCU, Infotainment). One spark in the wrong place, or reversing the polarity (mixing up Plus and Minus), can cause thousands of dollars in damage.
Follow this guide to do it safely.
What You Need
- Jumper Cables: Ideally thick ones. The cheap, thin cables sold at convenience stores often get too hot and melt if used on big engines.
- A Donor Car: A car with a working battery.
- Safety: Ensure both cars are in Park (or Neutral) with handbrakes on.
The “Red-Red, Black-Metal” Rule (Memorize This!)
The order matters. Do not let the clamps touch each other.
Step 1: Connect RED (+) to DEAD
Connect the Red clamp to the Positive (+) terminal of the dead battery.
Step 2: Connect RED (+) to DONOR
Connect the other Red clamp to the Positive (+) terminal of the good battery (donor car).
Step 3: Connect BLACK (-) to DONOR
Connect the Black clamp to the Negative (-) terminal of the good battery.
Step 4: Connect BLACK (-) to METAL (The Critical Step)
DO NOT connect the final Black clamp to the Negative terminal of the dead battery. Why? Because batteries emit explosive hydrogen gas. A spark near the battery could cause an explosion (rare, but possible). Instead: Connect the Black clamp to an unpainted Metal Surface on the dead car’s engine block (like a bolt or a bracket), away from the battery. This is called “Grounding”.
The Procedure
- Start the Donor Car: Let it run for 2-3 minutes. Rev the engine slightly (2000 RPM) to generate current.
- Start the Dead Car: Turn the key.
- If it starts: Great! Leave it running.
- If it simply clicks: Check your connections. Wiggle the clamps to get a better “bite”.
- If it cranks very slowly: The battery is extremely dead. Wait another 5 minutes with the cables connected to let it charge a bit.
- Disconnect in REVERSE Order:
- Remove Black from Metal.
- Remove Black from Donor.
- Remove Red from Donor.
- Remove Red from Dead.
Special Warning: Hybrids and EVs
- HEV/PHEV (Toyota Cross, Camry Hybrid): Most hybrids have a small 12V auxiliary battery (often in the trunk) that starts the computer, not the engine. You CAN jump start them, but be very gentle. Do not use them as a Donor car to jump start a big diesel truck—it can overload the hybrid system.
- EVs (Tesla, BYD): Generally, DO NOT use an EV to jump start another car. Their 12V systems are small and sensitive. However, if your EV’s 12V battery dies, you can jump start it using a regular gas car to wake up the screens.
Still Not Starting?
If you’ve tried this and it doesn’t work, chances are your battery is internally shorted (dead cell) or your starter motor is broken. Don’t force it. You might damage the starter.
Safety Checklist: What NOT to do
- NO Smoking: Batteries vent hydrogen gas.
- NO Touching: Do not touch the metal clamps of the jumper cables together while connected.
- NO Rain: Try to avoid jump starting in heavy rain if possible, or use an umbrella to keep the battery dry. Water + Electricity = Bad day.
- Remove Jewelry: Remove metal rings, watches, or bracelets. If a metal tool touches your ring and the battery terminal simultaneously, the ring can become red-hot instantly and cause severe burns.
Frequently Asked Questions (FAQ)
Q: Can I use a small car to jump start a big pickup truck?
A: Generally, NO. A small car (like a Yaris) has a small battery (45 Amps). A big truck (like a Fortuner/Ranger) needs a lot of power (80-90 Amps). Trying to draw that much current could damage the small car’s alternator or blow a fuse.
- Rule: The Donor car should have a battery equal to or larger than the Dead car.
Q: How long should I drive after a jump start?
A: At least 30 minutes. Drive at a steady speed if possible (not stop-and-go traffic) to allow the alternator to recharge the battery. Do not turn off the engine immediately!
Q: My car starts but dies as soon as I disconnect the cables. Why?
A: Your Alternator is likely dead. The car was running off the donor battery’s power. Once disconnected, it has no power source. A jump start won’t fix this. You need a tow truck or a mechanic to change the alternator.
Q: What is a “Jump Starter Power Bank”?
A: It’s a portable lithium battery gadget. We highly recommend every expat in Phuket buys one (Lazada/Shopee). It allows you to jump start your own car without needing a second car.
- Pro: Safe, easy, no need to beg strangers for help.
- Con: You must remember to keep it charged.
Stuck in the middle of nowhere? Don’t risk it. Call EV Phuket Roadside Assistance: 098-168-9907.
Final Safety Reminder: Always double check your connections before starting the engine to ensure safety. A secure connection prevents sparks and creates a better flow of electricity.