This content was compiled automatically and has not yet been reviewed by a technician. For reference only.
For reference only. Always confirm part numbers and procedures for your specific vehicle.
Fault diagnosis
Alternator does not charge or charges intermittently: wiring and belt checks
A conventional alternator does not charge or charges intermittently.
Alternator does not charge or charges intermittently: wiring and belt checks
Symptoms
- A conventional alternator does not charge or charges intermittently. [1]
Possible causes
- Poor charging circuit or ground connections, or a loose, slipping belt, may affect charging. [1]
Checks
- Check the battery and connections, measure voltage drop in the positive and negative circuits, and check belt tension and condition; use the vehicle manufacturer's standards. [1]
What to do
- Address confirmed corroded, loose or damaged connections; if belt or charging output abnormalities remain, continue inspection and repair according to the relevant vehicle manufacturer's service procedure. [1]
Applicability and limits
- Conventional engine belt-driven alternators; specific test standards are determined by the vehicle manufacturer's manual. No site brand/model dictionary mapping has yet been made; this cannot establish vehicle fitment. Scope: unknown [1]
Related part categories
- Alternator drive belts [1]
- Charging wiring harnesses and ground connectors [1]
Sources
[Source 1] DENSO: Alternator troubleshooting — What can go wrong and how to fix it; drive belt tension; 2022-03-31 (accessed 2026-10-30)
https://www.denso-am.eu/news/alternator-troubleshooting
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