# screwed up tach **URL:** \ **Category:** SON240sx Automotive\ **Created:** [March 13, 2007, 8:28am UTC](https://forums.speedlife.net/t/screwed-up-tach/104449 "2007-03-13T08:28:54Z")\ **Posts on this page:** 1\ **Showing post:** 9
**Author:** ![Silvia\_Drift](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/silvia_drift/32/5271_2.png) [@Silvia\_Drift](https://forums.speedlife.net/u/Silvia_Drift)\ **Post date:** [March 15, 2007, 11:08am UTC](https://forums.speedlife.net/t/screwed-up-tach/104449/9 "2007-03-15T11:08:30Z")
> [@I've never felt so sick in my life over a car.](https://forums.speedlife.net/t/ive-never-felt-so-sick-in-my-life-over-a-car/11717/4): > > what is Inst1? > > are you sure you connected all the same coloured wires at the body harness connector when you did the SOHC to DOHC swap? one of those is the tach wire so if you didn’t connect it then your tach won’t work. > > the tach signal should come from the ignition coil. > > if you’re sure that everything is in order then pull out your cluster and try to find the tach wire behind it, it will probably be the same colour as it is by the ECU. measure this wire and make sure it has the correct signal. if it does then your cluster is probably the problem. > > hope that helps. I have not directly checked the signal at the back of my tach but I will. The thing is, I thought that even if the tach wiring is screwed up, the SAFC 2 would get a signal since it is connected directly to the ECU. There is a value coming through the red/yellow wire which is the tach signal and this wire is connected directly to the ECU. Also, when my friend looked at the S13 wiring diagram, he said that if the fuel gauge signal is coming through, then the tach signal is also coming through. Oh, and I just checked the SAFC2 manual and its actually In-1 I was refering to and its not the tach signal, its actually the airflow signal. --- _[View the full topic](https://forums.speedlife.net/t/screwed-up-tach/104449)._