XxJenoxX
Skin Suit
- Joined
- Apr 25, 2010
- Location
- Pittsburgh, PA
Ok, so I've got something fun.
1990 240, m47. I believe the previous owner may have installed a big tach, and it appears he did do it correctly. Speedo is intermittent, but tach has always worked except for one instance where the needle responded to key power instead of rpm. Smacked the dash and it corrected, never happened again.
Fast forward to today. I pulled the cluster to do the odo gears. Reinstalled, everything wired up correctly. But now the tach isn't responding to rpm, but is to power. It's basically acting lile a voltmeter. When I turn the key, the needle immediately jumps to about 1k, then slowly drifts up to 2k as the alt charges. I've pulled it all out and rechecked any obvious misconnections. Pulling the tach sense wire off while it's running does nothing. Pulling the half-moon connector kills it (is this power?).
What the fresh hell is this and how do I fix it?
1990 240, m47. I believe the previous owner may have installed a big tach, and it appears he did do it correctly. Speedo is intermittent, but tach has always worked except for one instance where the needle responded to key power instead of rpm. Smacked the dash and it corrected, never happened again.
Fast forward to today. I pulled the cluster to do the odo gears. Reinstalled, everything wired up correctly. But now the tach isn't responding to rpm, but is to power. It's basically acting lile a voltmeter. When I turn the key, the needle immediately jumps to about 1k, then slowly drifts up to 2k as the alt charges. I've pulled it all out and rechecked any obvious misconnections. Pulling the tach sense wire off while it's running does nothing. Pulling the half-moon connector kills it (is this power?).
What the fresh hell is this and how do I fix it?