How to check why my car head light weak.

There are some causes why your car head light weak unless you accelerate the accelerator to rise up the RPM. Due to weak battery, poor contact of battery post to cable, defective alternator.

How to check why my car head light weak?

Model: Hyundai Sonata NF

Year Model: 2009

Fuel: Gasoline

Displacement: 2400cc

Subject: Weak a/c blower and weak lights unless accelerate to make bright.

1) Condition

1. A/C blower
2. Weak lights

2) Cause

1. Due to weak alternator charging.

3) Diagnosis

1. Scan tool check = No trouble code.
2. Check for current data = battery voltage is only 12 volt.
3. Check battery with battery tester = Good battery.
4. Check for wire connection,poor contact or corroded.= Ok
5. Check alternator pull out and put new one.
6. Check again with scan tool = Ok 13.7 Volt

4) Repair Guides

• Replace alternator assembly.

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