I have search many times and have not found a proper answer to my problem. I have a 88 crx HF and have installed a JDM EF9 cluster that has the electronic vss connection. The cluster works with no problems, I have installed a VSS onto my D-series transmission and the guage picks up the signal just fine. My problem is that the ECU with Hondata s300 does not pick up the vss signal like the cluster does. I figured it was a bad ecu at first but than I tried the ecu on a friends car and it picked up his signal with no problem. I checked voltage at the vss pin (b10 on obd1 ecu) and its a constant 13-14v. I read that the vss signal is suppose to pulse from 0-12v and thats how the ecu knows how fast your going. I have my vss power (Blk/Ylk) connected to the "while running" 12v source on the under dash fuse box, the signal (Orange) going to ecu and cluster (cluster reads speed just fine), and the black grounded to the transmission. Is there something that I am wiring wrong that the signal is not pulsing? Any suggestion will be greatly appreciated, I am trying to get this sorted out so that I can use boost by gear and launch control on Hondata s300 which are speed based/activated.

 

The factory cable tach generates a electronic VSS pulse, and has a wire that goes to the ecu from the cluster. You should have 12v + and ground going to the VSS in the trans, and the VSS signal going to the cluseter AND the ecu.

As far as the VSS signal, it is AC, meaning it fluctuates 12v +/- every half rotation, you can pick it up by pushing the car back and forth a few times.

Kirk R

 

So what your saying is that the cluster is not providing the pulse to the ecu to read properly? I have the vss signal going into the vss pin on the cluster, how does that signal re-route back to the ecu? Maybe that is what I am missing.

 

In the factory cluster harness, there is a wire (yellow/red I believe) that went from the origional tach to the ecu. The factory tach, although cable driven, generated an electronic VSS signal internaly and fed that electronic VSS signal back to the ecu. If you have the VSS wire you installed going to the tach VSS input on the back of the cluster, you should also have the factory VSS wire that goes to the ecu connected. I think thats your problem.

Hope that helps

Kirk R

 

What color is that sneaky little wire and where do I find it? I need it to hook up my eVSS also.

 

Speed Pulsar wire on instrument cluster harness, on the 8-pin plug it's yellow/red. That wire is connected to the ECU.

 

For cleaner wiring you can even run the newwire from your tranny VSS to the ECU and then carry the signal up to the JDM tach through the stock pulser wire.