Since i bought my 94 940 2 years ago I've had an intermittent fuel guage, warning lights, and a jumpy tach, also randomly my alternator would not work till I reved the engine up past 2k rpm's, due to a faulty connection on the instrument cluster. I always thought it was bad connections where the wires connect to the cluster but I found out that it was bad solder joints that where cracking and losing connection. I resoldered all the connections and found at least 3 that where cracked. So now my fuel guage works, my warning lights all work, my alternator always works when I turn the car on, and my tach is no longer jumpy. For anyone else having problems I suggest you try this

740 clusters also have the same type of plastic circuit board that 940's have so give it a try if you're having problems.

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