Sonata GLS V6-2.5L (2000)
PROM - Programmable Read Only Memory: All Technical Service Bulletins
O2 Sensor/PCM - High NOx Problem Diagnosis
Group: ENGINE ELECTRICAL
Number: 01-36-026
Date: NOVEMBER, 2001
Model: 2001 SANTA FE V6 & 1999-2001 SONATA V6
Subject
1999-2001 SONATA AND 2001 SANTA FE V6 NITROGEN
OXIDE (NOx) DIAGNOSIS
DESCRIPTION:
If a 1999, 2000, or 2001 V6 Sonata's or 2001 Santa Fe V6's Nitrogen Oxide (NOx) output is above specification but meets Carbon Monoxide (CO) and
Hydro-Carbon (HC) specifications, check the following:
^
Using the Hi-Scan Pro, check for front 02 sensor related codes (even if the check engine light is NOT on).
^
Using the Hi-Scan Pro, check the function of both front 02 sensors (Bank 1 and Bank 2). Use the Flight Record mode to record the sensor signals and
review the data graphically.
^
Both front 02 sensors should cycle between approximately 0.7V to 4.3V at the same rate. Note if one 02 sensor has a much lower amplitude range
than the other (for example 1.5 to 3.5 Volts, compared to 0.7 to 4.3 Volts).
^
At a steady 3000 RPM (vehicle stationary with no load), the front 02 signal should cross the 2.5V line approximately 10 times in five seconds (these
are called cross-counts). Note if the number of cross-counts is significantly less than 10.
REPAIR PROCEDURE:
Replace both front 02 sensors and reprogram the ECM as outlined in TSB # 01-36-024 (Santa Fe) and TSB # 01-36-023 (Sonata). These TSB's include
the necessary part and warranty information.