Vehicle: 1997 Ford Truck Ranger, 2WD, V6-3.0L,
VIN U, Automatic Transmission/Transaxle
Problem: Truck had DTCs P0135, P0141 & P0155.
The vehicle ran well but the customer’s concerns were the MIL was
on and there had been a noticeable drop in fuel economy.
Details: The tech found no power to O2 sensor
heaters. Checked relay and fuse – both were good.
Confirmed Repair: The tech inspected the
underside of the fuse box and found that the connections had
spread open where the fuse is installed. He repaired the
connections and tested for power to the O2 sensor heaters.
Battery voltage is now present to both O2 sensor heaters. The
DTCs were cleared and the tech performed a drive cycle. No DTCs
returned. The problem was resolved.