Tach, speedo dont work, radio and trim cuts in and out

[z86roc28]

The tach doesnt work--stays at 800 rpm but hour meter is on. Speedo doesnt move. radio works, then quits. Trim wouldnt work when I first got it on the water today, then worked fine. 2004 Regal 2000 4.3L gxi. Is there a central location that I should be looking for faulty connections?

 

[Don S]

Re: Tach, speedo dont work, radio and trim cuts in and out

Battery connections. They need to be tight, and I don't mean wingnut tight with your fingers. Dump the wingnuts, and put some regular nuts on the terminals and use a wrench to tighten them down. Oh, and make sure they are clean too.

 

[z86roc28]

Re: Tach, speedo dont work, radio and trim cuts in and out

Thanks Don--I would be thrilled if this works!! I am gonna go try it

 

[Fishermark]

Re: Tach, speedo dont work, radio and trim cuts in and out

If that doesn't do it, then I would look at the big round plug at the engine. Pull that apart and check for corrosion. Use some dielectric grease after cleaning and put it back together and see if that helps.

 

[z86roc28]

Re: Tach, speedo dont work, radio and trim cuts in and out

Where is this plug typically located?

 

[craze1cars]

Re: Tach, speedo dont work, radio and trim cuts in and out

Also follow your fat black ground wire from the battery to where it bolts to the engine block. This is your main ground connection. Disconnect, clean up corrosion with fine sandpaper or similar, reconnect.

Same for the other end of the fat red wire off the battery. Follow that to where it hooks up at the starter. You might need to disconnect and clean corrosion from this connection as well.

Also lay on your back and look up under the dash, you'll find a fuse block under there with main red wire coming in, and a main black wire going out (plus a whole bunch of other smaller wire connections). Do these connections appear tight & clean?

FWIW this all likely has nothing to do with your speedo not working. To fix that you probably will find you have a small plugged hole in the leading edge your your outdrive. likely needs to be cleaned out/blown out with compressed air. Your speedo is most likely a simple air pressure gauge, and it is not hooked up to your electronic system at all, except for the backlighting.

 

[z86roc28]

Re: Tach, speedo dont work, radio and trim cuts in and out

Tightened battery cables--same. Circle plug is ok. Speedo does have a pitot tube but I will check the outdrive for plugged holes.