Q: Is an HDM headlight driver module the same as a relay switch?

asked by on August 31, 2017

GM said the problem could be the Headlight Driver Module (HDM). Is that the same as the Low Beam Relay? Do I need another Quote? Over researched problem and got myself a bit confused, you think....I guess we'll find out tomorrow. Call if you need to. Thanks Barbara

My car has 157000 miles.
My car has an automatic transmission.

Unfortunately many manufacturers will call a part by one name while call it something else. However a module is a computer and a relay is more like a switch. If they recommended a module it is likely a computer failure.

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