# P0122 Error Code

**URL:** <https://community.cartalk.com/t/p0122-error-code/40275>\
**Category:** Maintenance/Repairs\
**Tags:** jeep\
**Created:** [December 2, 2009, 6:27pm UTC](https://community.cartalk.com/t/p0122-error-code/40275 "2009-12-02T18:27:21Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![hyliner](https://avatars.discourse-cdn.com/v4/letter/h/aca169/32.png) [@hyliner](https://community.cartalk.com/u/hyliner)\
**Post date:** [December 2, 2009, 6:27pm UTC](https://community.cartalk.com/t/p0122-error-code/40275/1 "2009-12-02T18:27:21Z")

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I just purchased a 2002 Jeep Wrangler Sahara Edition and noticed that the gas gauge won’t go all the way to the full mark. I also seem to be loosing power when maintaining highway speeds and get less than expected gas mileage. The check engine light has been going on and off. I checked the error code and it is P0122 which is the TPS. If I have the TPS replaced could that resolve the gas and power issues?

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**Author:** ![hellokit](https://avatars.discourse-cdn.com/v4/letter/h/6a8cbe/32.png) [@hellokit](https://community.cartalk.com/u/hellokit)\
**Post date:** [December 2, 2009, 7:22pm UTC](https://community.cartalk.com/t/p0122-error-code/40275/2 "2009-12-02T19:22:51Z")

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Code P0122 means that the signal voltage is low from the throttle position sensor (tps). This doesn’t mean that the tps is bad. It could be from a wire which has a poor, high resistance, connection. You can measure the circuit with a multimeter, if you want to know BEFORE you have changed the tps. Or, you can change the tps, and then, do the measurements.

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**Author:** ![hyliner](https://avatars.discourse-cdn.com/v4/letter/h/aca169/32.png) [@hyliner](https://community.cartalk.com/u/hyliner)\
**Post date:** [December 2, 2009, 7:27pm UTC](https://community.cartalk.com/t/p0122-error-code/40275/3 "2009-12-02T19:27:17Z")

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Thank you, I’ll check the voltage and see if that’s okay and then go from there.

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**Author:** ![cigroller](https://avatars.discourse-cdn.com/v4/letter/c/c68b51/32.png) [@cigroller](https://community.cartalk.com/u/cigroller)\
**Post date:** [December 2, 2009, 7:29pm UTC](https://community.cartalk.com/t/p0122-error-code/40275/4 "2009-12-02T19:29:11Z")

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Like hellokit said. The specs for testing the TPS should be in a repair manual (Haynes or Chilton’s are about $20 & worth the investment), although Autozone’s online repair manuals might also provide the specs ([http://www.autozone.com](http://www.autozone.com))

Other than that you just need a multimeter. I don’t need one regularly - just for the occasional home or car service/repair so I just bought a cheap $10 one that has been working admirably for quite some time.

PS - I’d also throw a new fuel filter on it just for good measure - surely can’t hurt.

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**Author:** ![hyliner](https://avatars.discourse-cdn.com/v4/letter/h/aca169/32.png) [@hyliner](https://community.cartalk.com/u/hyliner)\
**Post date:** [December 2, 2009, 7:35pm UTC](https://community.cartalk.com/t/p0122-error-code/40275/5 "2009-12-02T19:35:11Z")

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Thanks,  
I’ll get a mutimeter and check the voltage. and replace the fuel filter. I doubt its ever been changed the vehicle has just under 40,000 miles on it.