FredsHHR

So im having some bad luck with my LT at the moment. Last week I took it to my mechanic and had the O2 sensors and the Mass Air sensor changed because they were throwing a code. Two days later I go out to drive somewhere and the car will not shift out of low, the check engine light is on, the power steering is coming up on the LED display, and the speedo isn't working.
I have the codes scanned and find out that my biggest problem is a barely living battery. I also discovered that both front wheel speed sensors are out. I was told that this could cause the transmission to not come out of low...
Is there any truth to the wheel speed sensors causing the transmission not to shift, and why would both wheel speed sensors go out at the same time like this?

Lucky

Welcome to the site.

First thing to do is replace your battery. Failing battery's can make all kinds of storage things happen.

I do not believe the wheel speed sensors would be causing you trans shifting problem. The trans has its own speed sensor which also supplies the speed signal to the speedo

FredsHHR

What would cause my speedo to stop working? Any relation to the wheel speed sensors?

firemangeorge

Like Lucky said, 1st thing to do is replace the battery. HHR's can have all sorts of electrical gremlins because of a battery voltage issue.

Speedo not working could very well be because of the battery. It is electronic, not mechanical.

Also for reference. If you are looking for help or ideas and it involves CEL's or codes, it's best to include the actual code numbers in your post. Just posting a description of what the code is doesn't really help us try to help you.
Best to post up the code #'s (ex: P0001,P0002) in any future posts.

843de

aboard Fred, posts #2 and #4 kinda say it all, these Trucklets do the dangdest things with failing batteries.

donbrew

Replacing expensive parts "because they are throwing a code" is really bad practice. Did the mechanic suggest some troubleshooting to find the actual problem? If not, I suggest a new mechanic.

My wild guess is that the flex pipe cracked to cause those codes, but since you didn't post the codes......

Wheel speed sensors are input for the ABS system NOT the speedo.

New wild guess: When the yahoo was replacing parts he damaged a wire or left a wire near the exhaust pipe and it melted.

Or, replace the battery.

Oldblue

Welcome to the site! When you replace the battery leave it disconnected for 30 minutes, connect the positive cable first then the negative last ensure the fume tube is in place , and just a heads up get a proper sized battery for the HHR and not the cheap generic one from well certain stores! If you know who I mean!

Don06

The front wheel sensors are for the anti lock brakes and the traction control. If they sense that one wheel is turning faster than the other it will actuate the traction control which will control the transmission and engine speed. It should turn on a yellow TC light on the dash.

As has been mentioned, a code being set in the computer only means that the sensor is not reading within the range that it should be which can be caused by many different things.

843de

Very well said Don.

donbrew

A BTW, for you Great White North residents. A group 48 battery is about 1 inch longer than the group 90 stock battery, it has the vent system and 850 CCA vs 650 CCA stock.

I have not tried it, but it should fit.