2001 suburban warning lights

I checked the cables, no corrosion and tight as a drum. I connected an OBD II computer to the plug under the dashboard and the computer replied that there were no trouble codes present. Is OBDII the proper code reader? none of these lights were on before I replaced the battery. now I have constant ABS, flashing Service ride control, change engine oil. The battery has not gone dead as of yet but the ampmeter is charging at about 16.5-17 volts. I disconnected the pos terminal while the vehicle was running and it continued to run even with the lights on. Any suggestions? Thanks so much. Best Regards

If the voltage is really that high then you have a problem with the voltage regulator, which is most likely inside the alternator. Normally, the voltage should not be higher than 15 volts. If this is the case get it fixed ASAP as this kind of trouble can damage your battery and other things. You may also find out after that is fixed that the other issuses will go away. The high alternator voltage may be causing those other problems to appear.

When a battery is disconnected on some vehicles it causes computers/modules to go to sleep. Then when the battery is reconnected these computers/modules may or may not wake back up. If they wake up they may lose their learned programing. Sometimes it’s just a matter of driving the vehicle so the computers/modules can relearn their programing. Othertimes it requires that the computers/modules be reprogramed using a special factory scan tool.

The charging system in your vehicle utilizes a generator instead of an alternator. The output of the generator is controlled by the vehicle ECU. So if the output voltage is too high the ECU is no longer controlling the output voltage.

One thing that should never be done is disconnect a battery while the ignition switch is on or if the engine is running. Doing this can cause voltage spikes. And these voltage spikes can damage computers and modules.

Tester