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How to replace voltage regulator

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The voltage regulator ensures the irregular electrical supply from the engine is turned in to a smooth current to recharge the car battery. My battery was not recharging properly and after a while driving the red dashboard light would come on, telling me there was an electrical problem. After checking the battery was OK and changing the generator brushes I found out on the VZi Forums that the voltage regulator might be the problem and ordered a new one.

You will need:

  • New voltage regulator
  • Mid-sized screwdriver, mine needed a Philips-head (cross-head)
  • Pliers, preferably needle-nosed
  • How to replace the voltage regulator

Regulator is placed under the back seat. Lift up the bottom part of the seat and take it out of the car, revealing the battery on one side and voltage regulator on the other, under a cardboard flap. There are several wires going in to the voltage regulator and you don't want to mix them up. Therefore, we're going to transfer them one at a time. First, take off any screws that aren't needed from the new regulator. Now put the new regulator next to the old one and remove each cable from the old regulator, one at a time and screw or push them on to the new one. You might need the pliers to ease the wires off the old regulator, and to squeeze the wire contacts closed a little if they seem a bit loose when you put them on the tabs of the new unit. You might not be able to move all of the cables across if they are quite short. It's very important you don't mix them up, so transfer as many as possible and either label the wires that can't stretch or take a photo to make sure you can see where they're each supposed to go. Finally, unbolt the old regulator from the car and bolt the new one down in it's place. When I first drove around with my new regulator it gave off a little smoke. Apparently this is grease or sealant burning off the insides of the regulator so don't worry about it unless it continues after the first couple of miles. You might want to leave the rear seat out and go for a few laps around the block to let the sealant burn off and air out the car. That's it, you can now put the seat back in and get on with dubbing around.


electrics, voltage regulator