So, when the speedometer is inaccurate that could be a number of things, so we need to suspect the speed sensor first and foremost.
However, I would suggest checking the wiring and making sure there is no high resistance in the wiring. Basically, what would happen is the speed sensor is sending the correct signal but the resistance is altering the signal and so it reads inaccurately and normally much lower.
https://www.2carpros.com/articles/how-to-check-wiring
https://www.2carpros.com/articles/how-to-use-a-voltmeter
So, there are only three real causes for this. The speed sensor and the wiring as we talked to and then the last is the cluster.
So, we simply need to check the wiring and if you have replaced the speed sensor then we have a cluster issue.
Please let me know what questions you have. Thanks
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Friday, January 7th, 2022 AT 3:47 PM