CEL Code #5 O2 Sensors (1 Viewer)

[wpns4l]

I have a 93 80 series and today it threw code #5. I just replaced both O2 sensors about two months ago with Toyota ones as I was getting Code 25 Lean Mixture. Since putting the sensors in that code is gone and all was good till today.

Searching the forums comes up with nothing on code 5. Is it as simple as one of the sensors is already bad? Are their other systems that would throw this code like a bad fuse or bad wiring?

I wont be able to get into this till Wednesday or possibly next week so trying to get ideas before tearing into it from anyone who has had this code before. Nothing in the FSM on code 5 that i could find.

 

[baldilocks]

A quick search shows no obd1 code 5. You’ll need to read it again. If you still think it’s code 5 you could simply clear that code and keep running it waiting to see if the DTC light comes on again.

Is the vehicle running as it normally does?

 

[wpns4l]

Codes List:
OBD1 Codes
1Normal Condition.
2Air Flow Meter signal.
3Ignition signal.
4Engine Coolant Temperature Sensor signal.
5Oxygen Sensor.
6RPM signal (Crank Angle Pulse).
7Throttle Position Sensor signal.
8Intake Air Temperature Sensor signal.
9Vehicle Speed Sensor signal.
10Starter signal.
11Switch signal.
11ECU/ECM.
12Knock Control Sensor signal.
12RPM signal.
13Knock Control CPU (ECM).
13RPM signal.
14Turbocharger Pressure.
14Ignition signal.
21Oxygen Sensor.
22Engine Coolant Temperature Sensor signal.
23Intake Air Temperature Sensor signal.
24Intake Air Temperature Sensor signal.
25Air-Fuel Ratio Lean.
26Air-Fuel Ratio Rich.
27Sub Oxygen Sensor signal.
28No. 2 Oxygen Sensor signal.
31Air Flow Meter signal (Vacuum Sensor signal).
32Air Flow Meter signal.
34Turbocharger Pressure signal.
35Turbocharger Pressure Sensor signal.
35HAC Sensor signal.
41Throttle Position Sensor signal.
42Vehicle Speed Sensor signal.
43Starter signal.
51Switch signal.
52Knock Sensor signal.
53Knock Sensor signal.
54Inter-cooler ECM signal.
71EGR System.
72Fuel Cut Solenoid signal.
78Fuel Pump Control signal.
81TCM Communication.
83TCM Communication.
84TCM Communication.
85TCM Communication.

its 5 flashes no doubt

 

[OffRoadScott]

Best thing to do is check the FSM and see what it calls for as far as resistance on your O2 sensors and go from there.

 

[baldilocks]

Codes List:
OBD1 Codes
1Normal Condition.
2Air Flow Meter signal.
3Ignition signal.
4Engine Coolant Temperature Sensor signal.
5Oxygen Sensor.
6RPM signal (Crank Angle Pulse).
7Throttle Position Sensor signal.
8Intake Air Temperature Sensor signal.
9Vehicle Speed Sensor signal.
10Starter signal.
11Switch signal.
11ECU/ECM.
12Knock Control Sensor signal.
12RPM signal.
13Knock Control CPU (ECM).
13RPM signal.
14Turbocharger Pressure.
14Ignition signal.
21Oxygen Sensor.
22Engine Coolant Temperature Sensor signal.
23Intake Air Temperature Sensor signal.
24Intake Air Temperature Sensor signal.
25Air-Fuel Ratio Lean.
26Air-Fuel Ratio Rich.
27Sub Oxygen Sensor signal.
28No. 2 Oxygen Sensor signal.
31Air Flow Meter signal (Vacuum Sensor signal).
32Air Flow Meter signal.
34Turbocharger Pressure signal.
35Turbocharger Pressure Sensor signal.
35HAC Sensor signal.
41Throttle Position Sensor signal.
42Vehicle Speed Sensor signal.
43Starter signal.
51Switch signal.
52Knock Sensor signal.
53Knock Sensor signal.
54Inter-cooler ECM signal.
71EGR System.
72Fuel Cut Solenoid signal.
78Fuel Pump Control signal.
81TCM Communication.
83TCM Communication.
84TCM Communication.
85TCM Communication.

its 5 flashes no doubt

Is this a generic code list or an actual list of Toyota codes?

 

[jonheld]

Codes List:
OBD1 Codes

its 5 flashes no doubt

All OBD1 codes are a 2 digit number.
From the Toyota FSM:

 

[wpns4l]

Hmm, then it must be code 55. I could have sworn my fsm didn't show a 55 but maybe I misread.

Story is still the same I replaced both sensors and their wiring when I did the engine out last year. Have to see if one has come loose or something.

 

[jonheld]

Hmm, then it must be code 55. I could have sworn my fsm didn't show a 55 but maybe I misread.

Story is still the same I replaced both sensors and their wiring when I did the engine out last year. Have to see if one has come loose or something.

Well, since code 55 is referring to the #2 knock sensor, I would start there as opposed to an O2 sensor. But that's just me.