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Home >> Lexus >> 2007 >> GS 350 AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 9 (Engine Control System (3UZ-FE)) >> SFI System >> DTC P0420 Catalyst System Efficiency Below Threshold (Bank 1); DTC P0430 Catalyst System Efficiency Below Threshold (Bank 2) >> Monitor Result
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Monitor Result

WARNING: This page is about a different car, the 2007 Lexus GS 430. However, it is still accessible from the selected car via links, so may be relevant.

Refer to detailed information (see CHECKING MONITOR STATUS ).

The test value and test limit information are described as shown in the following table. Check the monitor result and test values after performing the monitor driven pattern (refer to "Confirmation Monitor").

Catalyst bank 1 - Using heated oxygen sensor on sensor 1 and 2 

TYPICAL MALFUNCTION THRESHOLDS CHART

MID TID Scaling Description of Test Value Minimum Test Limit Maximum Test Limit
$21 $A1 Multiply by 0.0003 [no dimension] Locus length ratio of heated oxygen sensor 1 and 2 Minimum test limit for catalyst Maximum test limit for catalyst
$21 $A2 Multiply by 0.0003 [no dimension] Voltage area ratio of heated oxygen sensor 1 and sensor 2 Minimum test limit for catalyst Maximum test limit for catalyst
$21 $A3 Multiply by 0.0003 [no dimension] Locus length ratio of heated oxygen sensor 1 and 2 Minimum test limit for catalyst Maximum test limit for catalyst
$21 $A4 Multiply by 0.0003 [no dimension] Heated oxygen sensor frequency ratio of sensor 1 and sensor 2 Minimum test limit for catalyst Maximum test limit for catalyst
$21 $A5 Multiply by 0.0003 [no dimension] Locus length ratio of heated oxygen sensor 1 and 2 Minimum test limit for catalyst Maximum test limit for catalyst
$21 $A6 Multiply by 0.0003 [no dimension] Voltage area ratio of heated oxygen sensor 1 and sensor 2 Minimum test limit for catalyst Maximum test limit for catalyst

Catalyst bank 2- Using heated oxygen sensor on sensor 1 and 2 

TYPICAL MALFUNCTION THRESHOLDS CHART

MID TID Scaling Description of Test Value Minimum Test Limit Maximum Test Limit
$22 $A1 Multiply by 0.0003 [no dimension] Locus length ratio of heated oxygen sensor 1 and 2 Minimum test limit for catalyst Maximum test limit for catalyst
$22 $A2 Multiply by 0.0003 [no dimension] Voltage area ratio of heated oxygen sensor 1 and sensor 2 Minimum test limit for catalyst Maximum test limit for catalyst
$22 $A3 Multiply by 0.0003 [no dimension] Locus length ratio of heated oxygen sensor 1 and 2 Minimum test limit for catalyst Maximum test limit for catalyst
$22 $A4 Multiply by 0.0003 [no dimension] Heated oxygen sensor frequency ratio of sensor 1 and sensor 2 Minimum test limit for catalyst Maximum test limit for catalyst
$22 $A5 Multiply by 0.0003 [no dimension] Locus length ratio of heated oxygen sensor 1 and 2 Minimum test limit for catalyst Maximum test limit for catalyst
$22 $A6 Multiply by 0.0003 [no dimension] Voltage area ratio of heated oxygen sensor 1 and sensor 2 Minimum test limit for catalyst Maximum test limit for catalyst