Viper's Voltage Chaos: ECU Failures & Power Surges

I faced a very similar electrical system problem with my 2005 Viper. After some basic knowledge working on cars, I determined it needed professional diagnosis. The symptoms matched yours exactly, unusual electrical failures, car electronics acting erratic, and voltage regulator issues causing power surges. The ECU kept throwing overvoltage codes despite a new battery. Took it to a specialized workshop where they diagnosed a heavily discharged battery. Even though the battery was new, an alternator failure had damaged it beyond repair. The constant power fluctuations from the faulty alternator had degraded the battery cells. The total repair came to 290€ including: Battery replacement, Alternator testing and repair, System diagnostic checks, Clearing fault codes Since the fix, all electrical systems have worked perfectly with no more unusual failures or voltage issues. To help troubleshoot your case better, could you share: Battery voltage readings at idle and rev, Whether your alternator has been tested, Age of current alternator, Any warning lights on dash, Specific error codes from ECU This would help determine if your issue matches what I experienced with my Viper.

Thanks for sharing your experience. My alternator tested at 13.2V idle and jumps to 15.8V when revving, which points to voltage regulation problems. The alternator is original with 115652 KM. Just had it tested at a shop that specializes in high voltage systems. Their circuit protection analysis showed the voltage regulator is failing intermittently, causing power surges through the car electronics. This explains the unusual electrical failures. Will replace the alternator assembly since the voltage regulator is integrated. Parts are ordered and scheduled for installation next week. Hoping this resolves the electrical issue completely. Last service was 3 months ago for regular maintenance, but they didnt catch this developing problem. The error codes are P0562 and P0563 related to system voltage.

Thanks for the voltage readings, those numbers definitely confirm what I experienced. The 15.8V spike under rev is a classic sign of a failing voltage regulator, just like what happened with my Viper. When my alternator was failing, it also showed perfect idle voltage but dangerous power surges under load. These voltage spikes can seriously damage the car electronics and circuit protection systems over time. My battery actually failed because it couldn't handle the constant high voltage stress. One important thing I learned: make sure they check all the major electrical connections during the alternator swap. My repair revealed some corroded ground points that were making the voltage regulation even more unstable. The shop should also verify the circuit protection components havent been damaged by the repeated power surges. Those P0562/P0563 codes are exactly what my ECU was throwing before the repair. After the new alternator was installed, all electrical systems returned to normal and the car battery maintained proper charge. Keep us updated after the repair. Would be interested to hear if your solution matches what fixed my Viper.

Thanks for the follow-up on the alternator test results. The voltage readings make the root cause clear now. My alternator tested at 13.2V idle and jumps to 15.8V when revving, which points to voltage regulation problems. The alternator is original with 115652 KM. Just had it tested at a shop that specializes in high voltage systems. Their circuit protection analysis showed the voltage regulator is failing intermittently, causing power surges through the car electronics. This explains the unusual electrical failures. Will replace the alternator assembly since the voltage regulator is integrated. Parts are ordered and scheduled for installation next week. Hoping this resolves the electrical issue completely. Last service was 3 months ago for regular maintenance, but they didnt catch this developing problem. The error codes are P0562 and P0563 related to system voltage. Thanks again for helping confirm the diagnosis through your similar experience.