wscheffer
Senior Member
Hello again,
The tachometer on my 1987 420 SEL has not functioned since I purchased the vehicle earlier this year. I want to isolate this problem. Would it be safe to connect the alligator clip of a lighted electrical probe to the wire that connects to the tachometer in the instrument panel and then touch ground (Earth as you call it) with the tip as the vehicle is running?
If the light flashes then the problem is the actual gauge and if it doesn’t then the problem is well...
Or am I wrong in my thinking and blow out my EZL?
The tachometer on my 1987 420 SEL has not functioned since I purchased the vehicle earlier this year. I want to isolate this problem. Would it be safe to connect the alligator clip of a lighted electrical probe to the wire that connects to the tachometer in the instrument panel and then touch ground (Earth as you call it) with the tip as the vehicle is running?
If the light flashes then the problem is the actual gauge and if it doesn’t then the problem is well...
Or am I wrong in my thinking and blow out my EZL?
