Speedometer question
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Joined: May 2008
Posts: 14,803
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From: Great Mills, MD
Jeff wallman, you speedo is calculated by the ECU. It gets speed input from all 4 wheels via the ABS sensors. It then averages the sensors and then sends a signal to the instrument cluster for it to indicated. Odds are, your problem lies with the instrument cluster and all you need to do is find a new servo to do the movement.
If you were to have a "sensor" error, you would be getting the check engine light and atleast 2 of the following codes (C1145, C1155, C1165, and/or C1175). When you have 2 wheel speed sensors (ABS) out, the car is not smart enough to figure out if the car is moving or stopped. So, it fails to the stopped state and makes the speedo indicate zero. So, if your check engine light is not on, then you have a bad servo most likely. You got 2 of the above codes, that is what you need to fix.
If you were to have a "sensor" error, you would be getting the check engine light and atleast 2 of the following codes (C1145, C1155, C1165, and/or C1175). When you have 2 wheel speed sensors (ABS) out, the car is not smart enough to figure out if the car is moving or stopped. So, it fails to the stopped state and makes the speedo indicate zero. So, if your check engine light is not on, then you have a bad servo most likely. You got 2 of the above codes, that is what you need to fix.
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Joined: Feb 2020
Posts: 46
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From: Michigan
Jeff wallman, you speedo is calculated by the ECU. It gets speed input from all 4 wheels via the ABS sensors. It then averages the sensors and then sends a signal to the instrument cluster for it to indicated. Odds are, your problem lies with the instrument cluster and all you need to do is find a new servo to do the movement.
If you were to have a "sensor" error, you would be getting the check engine light and atleast 2 of the following codes (C1145, C1155, C1165, and/or C1175). When you have 2 wheel speed sensors (ABS) out, the car is not smart enough to figure out if the car is moving or stopped. So, it fails to the stopped state and makes the speedo indicate zero. So, if your check engine light is not on, then you have a bad servo most likely. You got 2 of the above codes, that is what you need to fix.
If you were to have a "sensor" error, you would be getting the check engine light and atleast 2 of the following codes (C1145, C1155, C1165, and/or C1175). When you have 2 wheel speed sensors (ABS) out, the car is not smart enough to figure out if the car is moving or stopped. So, it fails to the stopped state and makes the speedo indicate zero. So, if your check engine light is not on, then you have a bad servo most likely. You got 2 of the above codes, that is what you need to fix.
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Joined: May 2008
Posts: 14,803
Likes: 4,099
From: Great Mills, MD
Jeff Wallman, a quick check you can do is to start with the car in the OFF position. Now, press and hold the TRIP button depressed. While still holding the TRIP button, turn the key to the RUN position. After about 3 seconds, you should see the info screen say "Engineering TEST" or something to that effect. Now, release the TRIP button. Press the TRIP button one more time, this should cause your instrument cluster to light up like a christmas tree (every light should come on so you can see if you have any failed lights). Press TRIP again, you should see all your gauges sweep from min to max and back to min. If you watch the speedo, that will tell you if your problem is in the instrument cluster or elsewhere (ie, if the speedo sweeps, you most likely have a problem elsewhere). I may have the two presses of the TRIP button backwards, but you will get the idea.
To exit this special mode, simply turn the car off or start the car.
To exit this special mode, simply turn the car off or start the car.
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