You will need: Phillips and flat-head screwdrivers, 13mm and 15mm socket heads, and an ohmmeter (autotester).
1. Remove the generator from the vehicle (see "Removal and installation the generator").
2. Remove the screw securing the back cover.
3. Unscrew the two nuts...
4. ...and remove the rear cover of the generator.
5. Remove the three mounting screws...
6. ...and remove the voltage regulator.
7. Check the ease of movement of the brushes in the brush holder and their protrusion. If the protrusion A of the brushes from the brush holder is less than 5 mm, replace the voltage regulator assembly with the brush holder.
8. Check the rotor winding resistance with an ohmmeter (tester) by connecting it to the contact rings. If the ohmmeter shows infinity, then there is a break in the windings and the rotor needs to be replaced.
9. Check the rectifier block diodes. Connect one wire to the rectifier block ground, the other to the diode terminal...
10. ...and then swap the wires. The diode should only allow current to flow in one direction. If the diode allows current to flow in both directions, it is faulty.
[Original publication on the website RENAULTBOOK]
11. Check the remaining diodes in the same way.
12. To replace the rectifier unit, use a screwdriver to loosen the twelve contacts...
13. ...unscrew the two mounting screws and remove the rectifier unit.
14. Assemble the generator in the reverse order of disassembly.