Diagnose and Repair Motorcycle Not Charging Battery #2 | Regulator | Rectifier | SYM Jet Power 125

Today, I want to show you how to diagnose and repair scooter SYM Jet Power 125 hard to crank/start/not charging the battery due to a faulty regulator rectifier. Common symptoms of the faulty regulator or rectifier, e.g., low battery voltage and charging system failure.

References:

1. SYM Jet 4 125 Manual
   
   

Step 1: Diagnosis motorcycle

1. My battery is not charging even when I start the motorcycle and can cause a low voltage/dead battery.
   
2. You can see the battery voltage at 12.22 V and not increasing.
   
3. After the diagnosis of my motorcycle, I found that my charging system had failed. 4 common places that need to be troubleshot are the alternator, regulator, fuse, and wiring/connector.
   

Step 2: Removal of regulator/rectifier

1. Disassemble the body cover in sequence 1 → 2 → 3 as shown in the figure below. You can watch my previous video or post on how to remove body cover step by step.
   
   
   
   
   
2. Remove the regulator/rectifier mounting bolt.
   
   
   
   
   
3. Disconnect the 4P connector on the regulator/rectifier.
   
   
   
   
   
4. Disconnect the connector of the resistor pin and starter pin.
   
   

   

   
   
5. Check voltage, continuity, and resistance value as shown in the figure below.
   
   

   
   
   

   My main wire circuit is in good condition (within the standard values), and there is no loose pin in the regulator/rectifier.
   
   
6. Check the resistance of the regulator/rectifier.
   
   
   
   
   

   Check the resistance between the terminals according to the table above. Make sure the positive and negative probe incorrect position according to the table.

   
   
   
   
   

   If the resistance values are exceeded or less than the standard value among the pins, replace the regulator/rectifier. In my case, my value is the open load or open circuit (OL). So I need to replace this regulator/rectifier.
   
   
7. Comparison between the new OEM regulator/rectifier and the original broken regulator/rectifier.
   
   

   
   
   

   The only difference is connector color (white color original and black color on OEM).
   
   

Step 2: Installation

1. Install the new OEM regulator/rectifier in the reverse order of removal.
   
   
2. Start and take the reading with a multimeter. You can see from the picture below the reading around 13 V ++ compared to before replacing the regulator rectifier.
   
   
   
   
   
   

The link tools and components replacement I used in this video are listed below:

Tools/Components/Items (Shopee):

1. Spanner Set
2. Screwdriver Set
3. Regulator or Rectifier (OEM)
4. Regulator or Rectifier (Original)

Tools/Components/Items (Lazada):

1. Spanner Set
2. Screwdriver Set
3. Regulator or Rectifier (OEM)
4. Regulator or Rectifier (Original)

Tools/Components/Items (Aliexpress):

1. Spanner Set
2. Screwdriver Set

Video:

That all from me. If you have any suggestions, please write in the comment section. Thank you for your time 👷.