Honda1

Ok i've read some threads on here about the TPS. I was driving and my CEL Light came on and the rpm's jumped and would shift real high. I got it to autozone i was 5 mins away. They checked it code was PO122 TP sensor circuit low voltage.

Open or short circuit condition
poor electrical connection
Faulty TP Sensor

Now how would i test to make sure there isn't a short circuit i know i need a multimeter but what number am i testing for? Also as luck would have it the damn light went off the next day.That really stumped me because i was just gonna replace the throttle body but now idk if i should. I don't want it shifting funny especially if i'm not driving. I haven't noticed any funny idleing except when it was real cold out. I sprayed some contact cleaner in the sensor and plug. Other then testing the wires i wonder if i should just wait to see if the cel comes back on.

Matt_75

Disregard the outside numbers. Use the inside one's when it refers to steps. HTH.

DTC P0122: TP Sensor Circuit Low Voltage

1. Turn the ignition switch ON (II).
2. Check the throttle position with the scan tool.

Is there about 10% or 0.5 V when the throttle is fully closed and about 90% or 4.5 V when the throttle is fully opened?
YES
- Intermittent failure, system is OK at this time. Check for poor connections or loose wires at the TP sensor and at the ECM/PCM.
NO
- Go to step 3.

1. 3. Turn the ignition switch OFF.
2. 4. Disconnect the TP sensor 3P connector.
3. 5. Turn the ignition switch ON (II).
4. 6. Measure voltage between the TP sensor 3P connector terminals No. 1 and No. 3.

TP SENSOR 3P CONNECTOR

Wire side of female terminals Is there about 5 V?
YES
- Go to step 7.
NO
- Go to step 14.

1. 7. Turn the ignition switch OFF.

1. 8. At the sensor side, measure resistance between the TP sensor 3P connector terminals No. 1 and No. 3 with the throttle fully closed.

TP SENSOR 3P CONNECTOR

Terminal side of male terminals Is there about 0.5-0.9 k ohms?
YES
- Go to step 9.
NO
- Replace the throttle body.

1. 9. Measure resistance between the TP sensor 3P connector terminals No. 1 and No. 2 with the throttle fully closed.

TP SENSOR 3P CONNECTOR

Terminal side of male terminals Is there about 4.5k ohms?
YES
- Go to step 10.
NO
- Replace the throttle body.

1. 10. Disconnect ECM/PCM connector A (31P).

1. 11. At the wire harness side, check for continuity between TP sensor 3P connector terminal No. 2 and body ground.

TP SENSOR 3P CONNECTOR

Wire side of female terminals Is there continuity?
YES
- Repair short in the wire between the ECM/PCM (A15) and the TP sensor.
NO
- Go to step 12.

1. 12. Connect ECM/PCM connector terminal A15 and body ground with a jumper wire.

ECM/PCM CONNECTOR A (31P)

Wire side of female terminals

1. 13. At the wire harness side, check for continuity between TP sensor 3P connector terminals No. 2 and body ground.

TP SENSOR 3P CONNECTOR

Wire side of female terminals Is there continuity?
YES
- Substitute a known-good ECM/PCM and recheck (see page 11-6). If symptom/indication goes away, replace the original ECM/PCM.
NO
- Repair open in the wire between the ECM/PCM (A15) and the TP sensor.

1. 14. Measure voltage between ECM/PCM connector terminals A10 and A20.

ECM/PCM CONNECTOR A (31P)

Wire side of female terminals Is there about 5 V?
YES
- Repair open in the wire between the ECM/PCM (A20) and the TP sensor.
NO
- Substitute a known-good ECM/PCM and recheck (see page 11-6). If symptom/indication goes away, replace the original ECM/PCM.

ezone

In order to set that code, the computer had to detect: output voltage from the TPS was 0.23 V or less for at least 2 seconds.

In order to turn the CEL off, the computer had to see 3 "consecutive good trips" without seeing that same fault. (CEL is turned off, but the code and FF data are retained in memory for a longer number of startups.)


Since the CEL is now off, that means everything related to the TPS is acceptable to the computer. You probably won't find anything wrong at all, if you test it now.

Wiring usually won't go bad, then magically heal itself.

Would have been nice to know what the freeze frame data was. That way we could see what the TPS was at when the code set.

If you want to test, you need a voltmeter and ideally you need to know how to backprobe a circuit while everything is connected and operable.

Almost all 3 wire sensors use the same things.
One wire will be a power (5V for this one) one will be a a ground, and the third will be the signal return to the computer-- (when unplugged, it will read either be 5v or ground, depending on the design of the computer. When plugged in it will read whatever the sensor output is.) Closed throttle should be 0.49v, wide open throttle will be around 4.5ish volts. Should be a smooth sweep when the throttle is slooowly opened and watching the meter.

But like I said, right now everything will test as "good".

If you don't have a scanner or code reader.......start it up and wiggle the wiring at the TPS and its harnesses. Then go look at your check engine light. If the CEL came back on while you were doing that, then you may be on to something with wiring. I doubt you will get any results like that though.

My bet is a bad TPS. They can be flaky like that.

HTH

Honda1

Ok so I haven't run any tests on it but I did jiggle the plug and the light came back on only this time I went back to autozone an they said it was the intake sensor which is weird. The light went out though about 20 mins later. I'm wondering if it is a bad tps maybe I should drive it to see if it happens again. If so i kno it's the tps? The wires are in great shape so is the plug.



Thanks for the help guys!

ezone

I can't believe wiggling the TPS would give you an IAT code unless you unplugged it to reach the TPS.
Stop believing the parts pushers at the Zoo.

Read the codes for yourself.

Get the REAL code numbers (Pxxxx format) and either google for yourself, or post them.

Get Freeze Frame data too, if possible.