VW Bora Starting Failure Points to Terminal 30 Issue

As a VW Golf 2002 owner, I encountered nearly identical starting problems last season. The voltage drop test revealed multiple issues in the charging system: Main problems found: Corroded battery terminals causing poor connection, Failing alternator not maintaining proper charge, Damaged wiring between the ignition switch and starter The diagnostic process involved: 1. Testing battery voltage (showed 10.8V instead of required 12.6V) 2. Checking fuse box connections for corrosion 3. Load testing the alternator 4. Measuring voltage drop across main power supply circuits The root cause was the alternator failing to maintain sufficient charge, which eventually led to complete battery failure. The battery terminals corrosion was accelerating the problem. This required replacing both the alternator and battery to restore proper starting function. Recommend getting these specific checks: Full charging system diagnostic, Terminal 30 circuit inspection, Alternator output testing under load, Battery load test, Ground connection resistance check This was a serious issue that could have left the car stranded if not addressed promptly. The symptoms match exactly what you describe with the engine barely turning over.

Thanks for sharing your experience. The detailed description helped identify the possible problems with my Bora. After reading about your charging system troubles, I suspect my case might be similar. The starter motor behavior sounds exactly like what I am experiencing. Did you remember what the total repair cost was? Also curious if any other electrical issues came up since fixing the alternator and battery. My power windows have been acting up too, so wondering if there might be a connection with the general power supply problems. The Terminal 30 check seems particularly relevant in my case. Did they mention anything specific about short circuit risks during diagnosis?

Glad my previous response helped identify the issue. Just got back from the mechanic where they fixed the Terminal 30 continuous plus interruption on my Golf. The charging system is now working perfectly. The total repair came to 290€, which covered fixing a heavily discharged battery. No other electrical faults have appeared since the repair, power windows, central locking, and all other systems are functioning normally. The wiring harness and all connections were thoroughly checked during diagnosis. Your power window issues could definitely be related to the electrical system problems. When the battery is weak, it often affects multiple systems. The mechanic should check the entire circuit breaker setup and fuse box connections while diagnosing the starting problems. Regarding short circuit risks, the diagnostic process includes comprehensive safety checks. The ignition switch and all related circuits are tested to prevent any potential electrical problems. Having a proper diagnosis is crucial since these issues can cascade into bigger problems if left unchecked.

After getting the feedback here, I decided to visit a different mechanic who specializes in VW electrical systems. The experience was much better than my previous attempts at getting this fixed. The mechanic performed a complete voltage drop test across all major circuits and found the alternator was only putting out 11.2V under load, way below spec. They also discovered significant corrosion in the fuse box that was causing additional resistance in the charging circuit. Total repair cost came to 450€ including: New alternator, Battery replacement, Cleaning all ground connections, Fixing corroded fuse box terminals The car starts perfectly now and all electrical issues including the power windows are resolved. The ignition switch and surrounding wiring were also inspected but found to be in good condition. Really glad I got detailed advice before going in. It helped me understand what to expect and made sure the proper diagnostic steps were followed. The short circuit risks were properly checked during testing, which gave me peace of mind about the repair quality.