i have 21-51 i dont have a book so i dont know what they are. can someone please tell me what they are ... thank you
need help with codes
- Thread starter onefstsupra89
- Start date
future reference looks here http://www.cygnusx1.net/Supra/TechTips/engine_error_codes.aspx
your codes are
21 Oxygen Sensor Signal
Diagnosis
* Detection of oxygen sensor deterioration.
Trouble Area
* Oxygen sensor circuit
* Oxygen sensor
* ECU
51 Switch Signal
Diagnosis
* No "IDL" signal, "NSW" signal or "A/C" signal to ECU, during diagnosis check.
Trouble Area
* A/C switch circuit
* A/C switch
* A/C amplifier
* Throttle position sensor circuit
* Throttle position sensor
* ECU
-Thomas
your codes are
21 Oxygen Sensor Signal
Diagnosis
* Detection of oxygen sensor deterioration.
Trouble Area
* Oxygen sensor circuit
* Oxygen sensor
* ECU
51 Switch Signal
Diagnosis
* No "IDL" signal, "NSW" signal or "A/C" signal to ECU, during diagnosis check.
Trouble Area
* A/C switch circuit
* A/C switch
* A/C amplifier
* Throttle position sensor circuit
* Throttle position sensor
* ECU
-Thomas
51 Switch Signal
Diagnosis
* No "IDL" signal, "NSW" signal or "A/C" signal to ECU, during diagnosis check.
Trouble Area
* A/C switch circuit
* A/C switch
* A/C amplifier
* Throttle position sensor circuit
* Throttle position sensor
* ECU
-Thomas
how can i trouble shoot this and how can i fix it?
Diagnosis
* No "IDL" signal, "NSW" signal or "A/C" signal to ECU, during diagnosis check.
Trouble Area
* A/C switch circuit
* A/C switch
* A/C amplifier
* Throttle position sensor circuit
* Throttle position sensor
* ECU
-Thomas
how can i trouble shoot this and how can i fix it?
Hey,
A code 51 is generally a sign of an improperly adjusted TPS. If you do a search for TPS adjustment, you will find a well documented method of how to adjust it and get rid of the code.
It is also a diagnostic tool for verifying that the AC clutch system is working correctly. If I turn on the AC and check my codes, I should get a code 51, to tell me that the AC clutch is engaged. If I didn't get a code 51, then I know that there is a problem with the AC.
Usualy, people don't have the AC turned on when they check codes, so 51 is telling them that the ecu is not getting an idle signal from the TPS. This can be due to a faulty tps, or simply that needs to be adjusted.
The symptoms of a mal-adjusted tps is a wandering idle, and sometimes stalling (usually stalling is worse with an auto trans)
Symptoms of a faulty tps is generally a terrible bucking/studdering under accelleration along with a poor idle.
I hope this helps,
-Jake
A code 51 is generally a sign of an improperly adjusted TPS. If you do a search for TPS adjustment, you will find a well documented method of how to adjust it and get rid of the code.
It is also a diagnostic tool for verifying that the AC clutch system is working correctly. If I turn on the AC and check my codes, I should get a code 51, to tell me that the AC clutch is engaged. If I didn't get a code 51, then I know that there is a problem with the AC.
Usualy, people don't have the AC turned on when they check codes, so 51 is telling them that the ecu is not getting an idle signal from the TPS. This can be due to a faulty tps, or simply that needs to be adjusted.
The symptoms of a mal-adjusted tps is a wandering idle, and sometimes stalling (usually stalling is worse with an auto trans)
Symptoms of a faulty tps is generally a terrible bucking/studdering under accelleration along with a poor idle.
I hope this helps,
-Jake
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It will also set it (51) if you touched thgas pedal/throttle, while you had the jumper wire in checking codes.
Thank you guys i checked the A/C and it works fine COOOOLLLLDDD are comes out, and the clutch does ingages it idels good and there is no wondering idle or anything of that matter but it normally idels about 1050 rpms i think is a bit high when driving it does feel like under power when boosting im only getting 7 psi i think is a clogged cats. im still getting the codes as of this morning.
7 psi is stock, what are your mods?
It should idle at 650, so my guess is that the previous owner was having idle problems and cracked the throttle plate with the adjusting screw so the car would idle good, albeit high.
When you turn the ignition from on to off, you should hear a clicking "chucka chucka" sound, which is the sound of a healthy idle speed controller "parking" or callibrating itself. If you hear it park, then I'd check around the throttle linkage and see if you can adjust it so that the throttle closes more completely. If you can close the throttle completely, then the code should go away, and it should idle around 650 instead of 1050.
That's a big assumption, but I've seen that exact situation in a few different supras.
If you don't hear a click, you'll need to check your idle speed controller (ISC) and make sure that the wiring for it is in good shape, and it would be a good idea to take it off and clean it out real good. It's the little black module located right behind the alternator on the intake manifold facing the valve cover, and has 1 large hose coming from it and two small coolant hoses on the underside of it.
Most idle problems are related to the ISC or are result of a vaccum leak, since you also have a code 51, I'd think ISC before a leak.
Hope this helps,
-Jake
It should idle at 650, so my guess is that the previous owner was having idle problems and cracked the throttle plate with the adjusting screw so the car would idle good, albeit high.
When you turn the ignition from on to off, you should hear a clicking "chucka chucka" sound, which is the sound of a healthy idle speed controller "parking" or callibrating itself. If you hear it park, then I'd check around the throttle linkage and see if you can adjust it so that the throttle closes more completely. If you can close the throttle completely, then the code should go away, and it should idle around 650 instead of 1050.
That's a big assumption, but I've seen that exact situation in a few different supras.
If you don't hear a click, you'll need to check your idle speed controller (ISC) and make sure that the wiring for it is in good shape, and it would be a good idea to take it off and clean it out real good. It's the little black module located right behind the alternator on the intake manifold facing the valve cover, and has 1 large hose coming from it and two small coolant hoses on the underside of it.
Most idle problems are related to the ISC or are result of a vaccum leak, since you also have a code 51, I'd think ISC before a leak.
Hope this helps,
-Jake