Speedometer and odometer not working... any ideas?

Kia Models Forum Optima
1

I’ve replaced the vehicle speed sensor (VSS), the PCM, and the instrument cluster on my 2008 Kia Optima (manufactured 02/08). The dealer inspected it but found no corrosion or damage. Still no luck fixing the speedo or odo. Has anyone dealt with this issue before? Any tips on what to check next?

2

Did you check the wiring harness for damage or loose connections? Sometimes a bad connection can cause this.

3

Sage said:
Did you check the wiring harness for damage or loose connections? Sometimes a bad connection can cause this.

Not yet. I suspect there might be an issue with the harness or maybe a spliced wire causing trouble. Thanks for the tip!

4

The P0501 code could also indicate a problem with the wheel speed sensor. Have you checked that yet?

5

SorentoSquad said:
The P0501 code could also indicate a problem with the wheel speed sensor. Have you checked that yet?

Good point! I’ll need to check the wheel speed sensor wiring to the ABS module. Thanks for mentioning this.

6

SorentoSquad said:
The P0501 code could also indicate a problem with the wheel speed sensor. Have you checked that yet?

Yeah, the wheel speed sensor often ties into the speedometer. Make sure to test for continuity and voltage while you’re at it.

7

If the cluster, PCM, and VSS are all fine, it might be an issue with the ABS harness. Did the dealer check that?

8

SchoolInSession said:
If the cluster, PCM, and VSS are all fine, it might be an issue with the ABS harness. Did the dealer check that?

The dealer didn’t mention checking the ABS harness. I’ll look into that as well. Seems like a solid lead.

9

SchoolInSession said:
If the cluster, PCM, and VSS are all fine, it might be an issue with the ABS harness. Did the dealer check that?

Sometimes there’s a pigtail connector near the ABS that could cause issues. Make sure it’s not spliced poorly.

10

I had a similar issue with my car. Turned out to be a bad connection at the PCM. Might be worth double-checking those connectors.

11

Gerald said:
I had a similar issue with my car. Turned out to be a bad connection at the PCM. Might be worth double-checking those connectors.

Thanks! I’ll add that to my checklist. It’s been a real headache trying to track this down.

12

If you’re testing continuity, don’t forget to check between the PCM and the cluster. It could narrow down the problem.

13

EmmanuelBrown said:
If you’re testing continuity, don’t forget to check between the PCM and the cluster. It could narrow down the problem.

That’s my next step. I’ve checked most of the connections, but I haven’t gotten to the cluster yet. Thanks for the suggestion.