Oops, I may have spoken too soon. Never owned a W126.

However, my W210 has a fan that draws air into the temp sensor and I remember it acting pretty funky when that fan quit. The W126 could have a similar setup.

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Rick Miley
2014 Tesla Model S
2018 Tesla Model 3
2017 Nissan LEAF
Former MB: 99 E300, 86 190E 2.3, 87 300E, 80 240D, 82 204D Euro
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