Question On Tire Pressure Monitoring:

I Was On The Interstate (I-77 - Charlotte), Tire Pressure Warning Light Illuminated. Oh No, Not Again!
Pulled Onto Shoulder, Did Visual Of Tires, Nothing Appeared Low.
As It Was Only 5 Miles To Dealer, I Drove There.
As I Waited For Service Tech To Check It Out, I Used My Tire Pressure Gauge To Check The Tires. The Front Tires Both Had 30 Psi, The Passenger Rear Had 27 Psi, The Driver Rear Had 40 Psi.
The Passenger's Rear Had A Flat (Roofing Nail) Only A Week Prior, And Since It Was The Lowest Reading (27 Psi) I Told The Service Tech That I Suspect This Tire Was Triggering The Sensor.
The Driver's Rear Had A (Screw) Flat About 4 Weeks Prior And I Never Checked The Psi After The Repair.
Well, The Service Tech Took The Car Into The Service Bays And Returned 20 Minutes Later And Informed Me That The High Pressure Tire (Driver's Rear - 40 Psi) Was Causing The Sensor Alert. I Told Him That The Tire Was Repaired 4 Weeks Ago And It Seemed Strange That I Was Just Now Getting The Alarm. The Tech Said To Drive The Car And If The Warning Light Came On He "would Check It Out Further".

I Took The Car Home And Used It This Weekend With No Problem.

I Checked The Service Manual And Owners Manual For The Tire Monitoring Sensor And There Is No Mention Of An Over-inflated Tire Causing The Sensor To Send An Alarm.

Has Anyone Got An Insight Into What May Have Happened And If The Diagnosis Is Correct. I, As I Sure Most Of You Too, Do Not Like Driving Without A "spare" And Running The Risk Of Shredding The Tire And Destroying The Rim.