<img height="1" width="1" style="display:none" src="https://www.facebook.com/tr?id=918799731584652&amp;ev=PageView&amp;noscript=1">
FCP Euro Service Kits

FCP Euro Kits

What actually happens when an alternator stops charging? Does it mean the whole alternator is trash, or can it be fixed? Volvo 850, S70, and even 960 alternators are pretty stout units - I've even heard of one lasting past 400,000 miles. Here's a quick way to reduce the cost of a potential alternator replacement and save yourself some labor, too. The procedure is roughly the same for '99+ Volvo vehicles, as well as other makes and models, since all alternators are quite similar.

Charging stops, the battery dies

In most cases, an alternator stops charging because the brushes wear down. Brushes are considered a wear item of the voltage regulator. When they get too short, they cannot make contact with the rotor shaft. Charging stops, your battery eventually dies, and the car is useless.

Since the brushes on these cars aren't individually replaceable, the next best thing is to replace the voltage regulator. It includes new brushes and will freshen the alternator up just right.

**Alternator removal is not strictly necessary, as long as you can get to these screws while it is mounted in the car. In some cases, turbo pipes as well as the dipstick tube will almost certainly need to be removed to make room for arms and tools. One tool is required: A phillips-head screwdriver with a good grip.

Regulator ReplacementIMG_0348

  1. Disconnect coolant temperature sensor connector.
  2. Remove the B+ cable from the alternator using a 13mm socket and stow the nut away safely.
  3. Gently pull the single, small spade-terminal wire off of the alternator.
  4. Remove the 3 small phillips head screws holding the cover onto the back of the alternator.
  5. Pry the tabs up holding the plastic cover on; pull it off, exposing the voltage regulator.
  6. Remove the two screws holding the voltage regulator to the body of the alternator.

IMG_0349 Remove the two screws holding the voltage regulator to the body of the alternator

The rotor shaft is now visible, as well as the round copper "pads" the brushes ride on. These do wear, but not at the rate of the brushes. In most cases, they will outlast the life of the vehicle, however an alternator rebuild will be required if these do wear down excessively, or the alternator's bearings have reached end-of-life.

[gallery ids="6026,6027,6028"]

At this point, installation is the reverse of removal. The new regulator will pop right in and allow the alternator to charge the car stronger than ever.

My regulator doesn't look like the one pictured

Volvo 850s did use different regulators throughout their production. The year of manufacture, and even the type of transmission specified different alternator amperage outputs throughout the years.

[gallery type="square" columns="2" ids="6029,6030"]

One regulator has the spade connector for the small wire on it, the other does not, as it is built into that model's alternator-body.

Regulator w/Spade terminal: Volvo Voltage Regulator (850 S70 V70 C70) Bosch 1197311520

Regulator w/o Spade terminal: Volvo Voltage Regulator (100AMP) Huco 9130518

Whichever regulator you need, you can be sure that it will have a brand spankin' new set of brushes that are much longer than what came off the car.

ezpass mailing address

 

 

Shop Volvo Electrical at FCP Euro

 


About the Author: Alex FiehlAF Headshot

Alex is FCP's Blog Editor and an IT technician from Endwell, NY. He has over 8 years of experience working on a wide array of import makes, but lately is partial to Volvo . For some reason he just purchased a Volkswagen, and is excited to see what breaks first.


author image
Written by :
Alex Fiehl


More Related Articles