My racecar is a '02 chassis with a '04 motor and a ver1 AEM EMS. The assist level at the track varies unpredictably (generally ends up requiring too much effort).

Shouldn't the AEM provide speed output to the EPS through the factory wiring harness?

 

is your battery good? I lost the alternator at the track and my power steering was getting heavier and heavier till the car died on grid

I pulled the EPS fuse and drove 3hours home on just the battery with no EPS.
After the trip I still had 30% battery left. One track session with EPS on nearly drained it completely so it seems to use a lot.

 

yes, battery good

 

I'm sorry I couldn't help but laugh at this "cave-man" response

 

The Vehicle Speed Sensor (VSS) located in the transmission sends it signal to the ECU and Speedo cluster. The speedo then cuts that signal down and feeds that lower rate signal to the EPS.

So to answer your question, NO, AEM EMS should not provide a signal to the EPS.

So that makes me wonder what you have done electrically in the car? Did you remove the OEM Speedo?

 

Very helpful - thank you.

Presumably the EPS speedo input is either missing or broken.

Stratocaster, do you happen to know the electrical specifics? Sounds like I'll need to split the output from the VSS and build a network (hopefully just a resistor) for the EPS input.

SoS built the car and replaced the OEM cluster with a Stack dash. The AEM records speed data that I have examined in the logs. I added a Zeitronix wideband O2 sensor input to the AEM but haven't touched anything else EMS related.

 

Yeah, I know the nitty gritty details. And it is not just a resistor. I have the part but I have not had time to install it yet. No motor in the car kinda makes fixing the EPS a waste.

You have to take the signal from the VSS and divide it by 40 to send the proper rate signal to the EPS. this is what you need, it was the one thing I found. If and When you order it, it must be configured to order. So spec it as "/40 with NO VRS"

http://www.race-technology.com/signal_cond...on_8_30630.html

 

Hey I think I bought a set of DTC60 from you before is that you? lol

Anyway, is your stack dash picking rev signal from the stock cluster harness? Cuz the EPS also picking engine speed signal from the cluster(yes cluster not ecu) I had same problem when i had my EMS installed and the stock tech didn't work, caused that the EPS was not working as well.

 

Yep, it was a set of DTC60 for Mitsu Evo.

I'm not sure how the Stack dash is wired, but the tach definitely works. Where did you take engine speed and vehicle speed from?

 

Both of those circuts are available form the OEM cluster connectors. I will be they tapped them right there.