Set the transmission to neutral, turn on the ignition.
Auxiliary wire (section not less than 4 mm) bridge terminals 30 and 50 of the starter.
If at the same time the starter works properly, then the reason lies in the wiring. If the starter does not work, it must be removed and checked.
When checking the connection, the wires must be well fixed and not oxidized.
| Symptom | Possible reason | Remedy |
| The starter does not rotate when the ignition is on | Low battery | Charge your battery |
| Bridge terminals 30 and 50 of the starter: the starter turns. Broken wire 50 in the ignition switch, defective ignition switch | Repair the break Replace damaged parts | |
| Broken wire or ground connection | Check the wires and their connection to the battery | |
| Low battery | Measure battery voltage or charge it | |
| High contact resistance due to weakening and oxidation of connections | Clean the battery terminals. Secure the connection between battery, starter and ground | |
| No voltage at terminal 50 (start relay) | Wire break, ignition lock defect | |
| Starter relay failure (diesel engine) | Check or replace relay | |
| Slow starter rotation, starter does not crank engine | Low battery | Charge your battery |
| Wrong oil filled into the engine | Fill with multigrade oil | |
| High contact resistance due to weakening and oxidation of the connection | Clean the terminals for connecting the battery and starter, fix the contacts | |
| The brushes do not fit into the commutator, are stuck in the guides, are worn, broken or dirty | Check, clean or replace carbon brushes, check guides | |
| Small distance between brushes and commutator | Replace carbon brushes and clean their guides | |
| Collector scratched, burned or dirty | Turn manifold or replace anchor | |
| No voltage at terminal 50 (less than 8 V) | Check ignition switch or start relay | |
| Start relay defect | Replace start relay | |
| The starter grabs, but does not pull, jerkily turns the engine | Reducer failure | Replace gearbox |
| Gear contamination | Clean the gears | |
| Flywheel ring gear damage | Rework ring gear, replace flywheel | |
| Gear does not disengage from flywheel | Dirty, damaged gearbox or screw splines of the armature shaft | Clean or replace gearbox |
| Start relay failure | Replace start relay | |
| Return spring damaged | Replace spring | |
| The starter works after releasing the ignition key | Start relay stuck | Switch off the ignition immediately, replace the start relay |
| Ignition switch won't turn off | Disconnect battery wires Replace ignition switch |