88 MJ Gauge Cluster Swap - Tach no worky

J

joshv98xj

NAXJA Forum User

Location

Bozeman, MT

• Dec 22, 2006

• #1

I just did the boneyard gauge swap to trade my massive fuel gauge for a tach, but my tach doesn't seem to be working at all? Did I not get the right gauge cluster? Is there some other sensor or sending unit I need to buy? Any help would be appreciated. Thanks-

JOSH

 

87manche

NAXJA Forum User

Location

Ohio

• Dec 22, 2006

• #2

what motor do you have, and what motor did the donor vehicle have?

 

J

joshv98xj

NAXJA Forum User

Location

Bozeman, MT

• Dec 22, 2006

• #3

Whoops, I left that out, didn't I? They were both 4.0, both Renix. Mine is 5sp, the donor was an auto.

 

87manche

NAXJA Forum User

Location

Ohio

• Dec 22, 2006

• #4

should make any difference then.
it "should" have been a drop in install, but if it's not working you need to verify that the tach has a connection to the coil.
I believe it's a green wire.

 

J

joshv98xj

NAXJA Forum User

Location

Bozeman, MT

• Dec 23, 2006

• #5

I just checked, the green wire is there and plugged in, how do I go about testing if it is sending some type of signal? I was looking thru a FSM pdf file I have, and one of the diagrams of all the sensors shows an "engine speed sensor." Could that have anything to do with this?

 

87manche

NAXJA Forum User

Location

Ohio

• Dec 23, 2006

• #6

the engine speed sensor is the CPS, unrelated.
the tach get's it's signal directly from the coil. I'd clean the contacts and check for continuity.

 

J

joshv98xj

NAXJA Forum User

Location

Bozeman, MT

• Dec 23, 2006

• #7

How do I go about checking for continuity? Electrical is not really my thing, but I can figure it out......

 

W

wish

NAXJA Forum User

Location

Austin, MN

• Dec 24, 2006

• #8

Kind of a long shot, but a lot of electric tachs grab their power from the courtesy lamps. If your interior lights aren't working when you open the door, check the fuses to be sure you haven't popped one and then see if the tach is working.