Very Odd - Gauge Cluster/Dash/Engine? Electrical Trouble
 

Wife states while driving yesterday (84 deg. day) noticed the A/C randomly working/not working. Then noticed gauge (all?) cluster notification lights on and RPM & Speedo needle sweeping down/up (with no accelerator movement). Vehicle seemed to keep running/driving fine. I test drove the vehicle later and did not see any anomalies until placed in the gear selector in PARK, at which time the engine shut off (with key still in on position) and all the gauge lights illuminated. Turned key to off and vehicle restarted fine with no CEL (check engine light). Also, engine may have not wanted to start for a few seconds on a couple test startups. Checked for codes with simple scan tool. Only SRS dash light stays steady on. 215,000 miles, no vehicle work done in recent past. Battery good charge state, newer Optima.

Anybody have any ideas? Is there a voltage regulator feeding the dash system? Vehicle computer issue? Concerned with vehicle leaving someone stranded if engine fails to start.

Thank you, Mark

Voltage is regulated by the battery and alternator, so use a volt meter to test the battery voltage while the engine is running.

When the car stalled out when you put into park, did the gauge cluster behave like you turned the key to the II (on) position, but did not try to start the car, where the check engine light does the bulb check?

Thank you for the reply. 11.95 Volts engine off & 14.34 V at fast idle across the battery terminals. When car stalled out when placed in park, all gauge cluster light came on like when key turned to II (2nd click).

11.95V is slightly low. A fully charged battery is 12.6V. If this were my car, I'd disconnect the battery cable and clean all ends of both battery cables, bolts and eyelets with a wire brush or sandpaper to ensure you have a good connection. It might be worthwhile to stop by a parts store or a shop and have them test the battery/alternator (and starter while you are there).

Just from your description, you lost voltage and shut down the car. It sounds like a possible poor contact in the electrical portion of the ignition switch. Before simply replacing, start the car and shake the key. If the car stalls out, then you pretty much verified the ignition switch has poor/worn contacts. If the car doesn't stall, it does not necessarily rule out the ignition switch.

Update - Problem apparently solved.
 

Update - Cleaned battery cable connections with 220 Grit sand paper & CRC Lectra-Motive spray cleaner (pos. & neg. cables at both ends). Battery end of clamps were somewhat dirty & positive clamp was somewhat loose. Reassembled and tightened clamps properly. The car has operated flawlessly since.

Thank you PAhonda for the advice and taking time to help find the solution.

very similar problem check all fuses. For me fuse #5 interior. My led reverse lights went out and kept shorting that same fuse. Replaced lights new fuse. All new. If not yea make sure the battery terminals andSANDPAPERED. If not you have a wiring issue most likely. And need to take it in