DTC P0146 HO2S Circuit Insufficient Activity Bank 1 Sensor 3. Chevrolet Camaro 1998

For 1990-2009 cars only

Makes 🢒 Chevrolet 🢒 1998 🢒 Camaro 🢒 DTC 🢒 DTC P0146 HO2S Circuit Insufficient Activity Bank 1 Sensor 3

Engine Controls Components
HO2S Sensors
OBD II Symbol Description Notice
Handling ESD Sensitive Parts Notice

Circuit Description

To control emissions of Hydrocarbons (HC), Carbon Monoxide (CO), and Oxides of Nitrogen (NOx), a three-way catalytic converter is used. The catalyst within the converter promotes a chemical reaction which oxidizes the HC and CO present in the exhaust gas, converting them into harmless water vapor and carbon dioxide. The catalyst also reduces NOx, converting it to nitrogen. The PCM has the ability to monitor this process using the Bank 1 HO2S 3 heated oxygen sensor. The Bank 1 HO2S 3 sensor produces an output signal which indicates the oxygen storage capacity of the catalyst; this in turn indicates the catalyst's ability to convert exhaust gases efficiently. If the Bank 1 HO2S 3 signal voltage remains at or near the 450mV bias for an extended period of time, DTC P0146 will be set.

Conditions for Setting the DTC

•	No TP sensor, EVAP system, EGR Pintle, misfire, IAT sensor, MAP sensor, fuel trim, fuel injector circuit, ECT sensor, CKP Sensor, or MAF sensor DTCs are set.

•	System voltage is greater than 9 volts.

•	The following engine run time requirements are met:

-	Manual Transaxle - 4 minutes.

-	Automatic Transaxle - 3 minutes.

•	Bank 1 HO2S 3 signal voltage remains between 425 mV and 475 mV for longer than 7.5 minutes.

Action Taken When the DTC Sets

•	The PCM will illuminate the MIL during the second consecutive trip in which the diagnostic test has been run and failed.

•	The PCM will store conditions which were present when the DTC set as Freeze Frame and Fail Records data.

Conditions for Clearing the MIL/DTC

•	The PCM will turn the MIL OFF during the third consecutive trip in which the diagnostic has been run and passed.

•	The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.

•	The DTC can be cleared by using the scan tool Clear Information function or by disconnecting the PCM battery feed.

Diagnostic Aids

Check for the following conditions:

•	Corroded exhaust flange bolts - Using a J 39200 DMM, ensure that continuity exists between the engine block and the heated oxygen sensor shell. If resistance is excessively high, replace corroded exhaust flange attaching hardware as necessary.

•	Poor connection at the PCM - Inspect harness connectors for the following conditions:

-	Backed out terminals.

-	Improper mating.

-	Broken locks.

-	Improperly formed or damaged terminals.

-	Poor terminal to wire connection.

•

Faulty HO2S heater or heater circuit - With the ignition ON the HO2S voltage displayed on a scan tool should gradually drop to below 300mV or rise to above 600mV. If not, disconnect the HO2S and connect a test light between the HO2S ignition feed and heater ground circuits. If the test light does not light, repair the open ignition feed or sensor ground circuit as necessary. Refer to Wiring Repairs . If the J 35616-200 test lamp lights and the HO2S signal and low circuits are OK, replace the HO2S. Refer to Heated Oxygen Sensor Replacement

•	Intermittent test - With the ignition ON, monitor the HO2S signal voltage while moving the wiring harness and related connectors. If the fault is induced, the HO2S signal voltage will change. This may help isolate the location of the malfunction.

Test Description

Number(s) below refer to the step number(s) on the Diagnostic Table:

If the DTC P0146 test passes while the Fail Records conditions are being duplicated, an intermittent condition is indicated. Review the Fail Records vehicle mileage since the diagnostic test last failed. This may help determine how often the condition that caused the DTC to be set occurs.

This vehicle is equipped with a PCM which utilizes an Electrically Erasable Programmable Read Only Memory (EEPROM). When the PCM is being replaced, the new PCM must be programmed.

DTC P0146 - HO2S Insufficient Activity Bank 1 Sensor 3

Step	Action	Value(s)	Yes	No
1	Was the Powertrain On-Board Diagnostic (OBD) System Check performed?	--	Go to Step 2	Go to the Powertrain On Board Diagnostic (OBD) System Check
2	Engine at operating temperature Operate engine above 1200 RPM for at least two minutes Does scan tool indicate Bank 1 HO2S 3 voltage varying outside the specified values?	424-475 mV	Go to Step 3	Go to Step 4
3	Turn ON the ignition switch. Review and record scan tool Fail Records data and note parameters. Operate vehicle within Fail Records conditions as noted. Using a scan tool, monitor Specific DTC info for DTC P0146 until the DTC P0146 test runs. Does the scan tool indicate DTC P0146 failed this ignition?	--	Go to Step 4	Go to Diagnostic Aids
4	Turn ON the ignition switch. Disconnect Bank 1 HO2S 3. Jumper the HO2S signal and low circuits (PCM side) to ground. Using a scan tool, monitor Bank 1 HO2S 3 voltage. Is Bank 1 HO2S 3 voltage below the specified value?	150 mV	Go to Step 8	Go to Step 5
5	Remove the jumper wire from the Bank 1 HO2S 3 Signal Circuit (leave the Bank 1 HO2S 3 low circuit connected to ground). Using a J 39200 DMM, measure voltage between the Bank 1 HO2S 3 signal circuit (PCM side) and the Bank 1 HO2S 3 heater ground circuit. Does Bank 1 HO2S 3 signal circuit voltage measure near the specified value?	450 mV	Go to Step 6	Go to Step 7
6	Turn OFF the ignition switch. Disconnect the PCM. Check continuity of the Bank 1 HO2S 3 low circuit. If the Bank 1 HO2S 3 low circuit measures over 5 ohms, repair open or poor connection as necessary. Refer to Wiring Repairs . Was Bank 1 HO2S 3 low circuit problem found and corrected?	--	Go to Step 15	Go to Step 9
7	Turn OFF the ignition switch. Disconnect the PCM and check continuity of the Bank 1 HO2S 3 signal circuit and the Bank 1 HO2S 3 low circuit. If the Bank 1 HO2S 3 signal or low circuit measures over 5 ohms, repair open or poor connection as necessary. Refer to Wiring Repairs . Was a problem found?	--	Go to Step 15	Go to Step 10
8	Check for a poor Bank 1 HO2S 3 signal or low circuit terminal connection at the Bank 1 HO2S 3 harness connector. If a problem is found, replace terminal(s) as necessary. Refer to Wiring Repairs . Was a problem found?	--	Go to Step 15	Go to Step 11
9	Check for poor Bank 1 HO2S 3 low circuit terminal connection at the PCM. If a problem is found, replace terminal(s) as necessary. Refer to Wiring Repairs . Was a problem found?	--	Go to Step 15	Go to Step 11
10	Check for poor Bank 1 HO2S 3 signal and low circuit and the Bank 1 HO2S 3 low circuit for a poor terminal connection at the PCM. If a problem is found, replace terminal(s) as necessary. Refer to Wiring Repairs . Was a problem found?	--	Go to Step 15	Go to Step 12
11	Replace Bank 1 HO2S 3. Refer to Heated Oxygen Sensor Replacement . Is the action completed?	--	Go to Step 15	--
12	Replace the PCM. Important: Replacement PCM must be programmed. Refer to Powertrain Control Module Replacement/Programming . Is the action complete?	--	Go to Step 15	Go to Step 13
13	Check for poor Bank 1 HO2S 3 signal circuit terminal connection at the PCM and replace terminal if necessary. Refer to Wiring Repairs . Did the terminal require replacement?	--	Go to Step 15	--
14	Locate and repair cause of high resistance (corroded exhaust flange bolts, separated exhaust flange). Is the action complete?	--	Go to Step 15	--
15	Turn ON the ignition switch. Review and record scan tool Fail Records data and note parameters. Clear DTCs Operate vehicle within Fail Records conditions as noted. Using a scan tool, monitor Specific DTC info for DTC P0146 until the DTC P0146 test runs. Does the scan tool indicate DTC P0146 failed this ignition?	--	Go to Step 2	System OK