P0654 Engine Speed Output Circuit (HELP!!)
Thread Starter
Melting Slicks
Joined: Feb 2001
Posts: 3,376
Likes: 4
From: Hershey, PA, USA
Cruise-In VI Veteran
St. Jude Donor '12
P0654 Engine Speed Output Circuit (HELP!!)
Ok started the car up today and the Tach went up like usual but then stayed at zero, restarted teh car, nothing still dead. So i checked the codes, i am getting
P0654 Engine Speed Output Circuit
What do I do fix this one?
P0654 Engine Speed Output Circuit
What do I do fix this one?
Melting Slicks
Joined: Aug 2001
Posts: 3,047
Likes: 124
From: Wichita KS
Re: P0654 Engine Speed Output Circuit (C5kid)
Ok started the car up today and the Tach went up like usual but then stayed at zero, restarted teh car, nothing still dead. So i checked the codes, i am getting
P0654 Engine Speed Output Circuit
What do I do fix this one?
P0654 Engine Speed Output Circuit
What do I do fix this one?
This might be caused by debris from the PCM connector surfaces. Also inspect the connector gaskets as the gaskets prevent contaminate getting into the PCM.
Diagnosis tests will check for the circuit being open or shorted to ground or voltage. The circuit is tested with a signal generator to generate a tachometer signal. The problem is then isolated to the Instrument Panel Cluster (IPC), poor connections, or the PCM.
I would check the connectors/wires for signs of obvious problems (corrosion/debris). A Service Manual would be helpful.
Drifting
Joined: Oct 2003
Posts: 1,540
Likes: 0
From: bloomfield nj
Re: P0654 Engine Speed Output Circuit (C5kid)
you lost the tach signal between the pcm and cluster.if you clear the fault,does the tach work?the signal goes from the pcm to the cluster[junctions through the fuseblock under the hood].i would check the connections.the pcm is seeing the engine speed,but not seeing the pulse out to the cluster.has anybody had the cluster out?if so,maybe you have a bad connection at the cluster.if wiring is ok,either the pcm or cluster tanked.i think the dealer has a tester that plugs in at the pcm connector that generates a tach signal to the cluster.if the tach works with the tester,the pcm tanked.
Thread Starter
Melting Slicks
Joined: Feb 2001
Posts: 3,376
Likes: 4
From: Hershey, PA, USA
Cruise-In VI Veteran
St. Jude Donor '12
Re: P0654 Engine Speed Output Circuit (C5kid)
Thank you guys, very helpful!!! But I fixed it the Bubba way!!! Got pissed started the car and smacked the dash w/ my hand :smash: WAMOO!!!
Tach bounced back to work!!! and hasn't given me a problem since, there is probally a loose wire back there so this weekend I will tear the dash apart and check it out.
Tach bounced back to work!!! and hasn't given me a problem since, there is probally a loose wire back there so this weekend I will tear the dash apart and check it out.
