XS Power XSP320-311 Controller and Harness for GM "SI" Series Alternators (1969 to 1988), Blue Display
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What's Inside?
- • Controller and Harness
- • Owner's Manual
Smart Voltage Control for GM SI Alternators
Give classic GM charging systems a modern performance upgrade with the XS Power XSP320-311. This controller and harness is engineered for GM “SI” Series alternators from 1969–1988, offering configurable voltage control across 12V, 14V, and 16V setups.
Frequently Asked Questions (FAQ)
- • Why does the XSP320-311 voltage fluctuate?
Users have reported voltage moving above and below the selected setting. Alternator temperature and VCM behavior can both affect readings.
- • Why won't my VCM change the voltage?
A real user reported pressing the adjustment controls without getting any voltage change. The VCM settings, wiring, and alternator should be checked first.
- • Why is my charging voltage suddenly too high?
Users have reported VCM systems reaching unexpectedly high voltage, including readings around 15V or more. This should be investigated immediately to protect connected electronics.
- • Can cold temperatures affect the voltage?
Yes. Users have noted that alternator voltage can be higher during cold starts and gradually change as the alternator warms up.
- • Why are my electronics cycling after installation?
One user reported aftermarket electronics repeatedly turning on and off when the VCM voltage became excessive.
- • Could voltage spikes put my amplifier into protection?
Yes. A user reported voltage spikes during changes in bass demand that caused equipment to enter protection.
- • Why does my alternator stop charging with the VCM connected?
A real VCM user reported an alternator shutting off after the controller was connected. Bypassing the VCM can help determine whether the problem is the controller or alternator.
- • Why does my VCM read differently while driving?
Alternator output can change with engine speed, temperature, and electrical demand, so the displayed voltage may not remain perfectly constant.
- • Can incorrect VCM settings cause overcharging?
Yes. Users have reported unusually high output after installation, making correct configuration and voltage verification especially important.
- • What should I check if my XSP320-311 seems faulty?
Start with the alternator, VCM wiring, settings, and actual voltage using a reliable meter. Real users have found that bypassing the VCM can help isolate an alternator-related problem.
Features:
- Classic GM Application: Made for 1969–1988 GM “SI” Series alternators.
- Integrated Controller & Harness: Simplifies VCM installation and voltage management.
- Wide 10–20V Range: Built for versatile charging configurations.
- 12V Voltage Mode: 14.2V–15.2V programmed adjustment range.
- 14V/16V Voltage Mode: 14.2V–19.5V programmed adjustment range.
- Selectable Settings: Dip switches help match the controller to your system.
- Performance Electrical Control: Designed for custom and upgraded charging builds.
- UPC: 692209051251
- Weight: 10
- Authorized Internet Dealer
Warranty: 2 Year(s) Warranty.
This item is accompanied by a manufacturer's warranty. If it is found to be defective, it may be returned to OnlineCarstereo.com for replacement within 2 Year(s) from the original date of purchase with proper return authorization.
