Mo Murphy Posted March 14, 2018 Share Posted March 14, 2018 I'm putting a 3.9 14 cux V8 in my 90 shortly. I'm using TD5 instruments and YBE100530 speedo transducer. Will the transducer produce a suitable signal for the 14 cux ecu ? Mo Quote Link to comment Share on other sites More sharing options...
Ex Member Posted March 14, 2018 Share Posted March 14, 2018 (edited) I doubt the hall effect sender will work. The 14CUX used a reed switch type of transducer with an inline resistor, giving a 12V pulse. YBE100540 with a resistor will work, but it probably won't run the TD5 speedometer. It will work, though, with an aftermarket VDO speedometer. Edited March 14, 2018 by Red90 1 Quote Link to comment Share on other sites More sharing options...
Mo Murphy Posted March 14, 2018 Author Share Posted March 14, 2018 That's interesting Red90, very interesting indeed 👍 Thanks Mo Quote Link to comment Share on other sites More sharing options...
Mo Murphy Posted March 14, 2018 Author Share Posted March 14, 2018 Red, can you see any issue with taking 2 signal feeds from the transducer, one with a resistor in it for the 14CUX and one for the speedo, assuming I could get it recalibrated to run on double the pulses ? Cheers Mo Quote Link to comment Share on other sites More sharing options...
Ex Member Posted March 14, 2018 Share Posted March 14, 2018 It works fine as I've shown it with an aftermarket VDO speedo. I've personally set one up this way. The resistor is needed because the 14CUX does not limit the current and will fry the transducer. If you open up the VSS that came with 14CUX vehicles, you will find it is a transducer just like YBE100540 with a 120 Ohm resistor inline. That is the other option as well, use the VSS box from an early RRC or Disco. I have no idea if the TD5 speedo can be made to work with this type of signal. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted March 14, 2018 Share Posted March 14, 2018 You could get massively high-tech and use a transistor fed from the 5v regulated line to pull a 12v line down via a resistor to create a 12v pulsed line. Or if memory serves, the speed signal isn't actually required for the 14CUX to work. Quote Link to comment Share on other sites More sharing options...
Mo Murphy Posted March 14, 2018 Author Share Posted March 14, 2018 Thanks for clarifying that Red90, I'm pretty certain that the electronic TD5 speedo can be calibrated to run on the 540 transducer and I can't see both the limited supply to the ecu and the speedo drawing too much current through the transducer It does seem that you have provided the solution. I'm obliged to you Sir Mo Quote Link to comment Share on other sites More sharing options...
Mo Murphy Posted March 14, 2018 Author Share Posted March 14, 2018 Me and hi-tech don't really mix, fridge 😉 Even this level of electrickery frightens me 😊 Mo Quote Link to comment Share on other sites More sharing options...
Anderzander Posted March 14, 2018 Share Posted March 14, 2018 Wow Mo - I thought you and your 200tdi were happily married !? Quote Link to comment Share on other sites More sharing options...
Retroanaconda Posted March 14, 2018 Share Posted March 14, 2018 There is a function on the Td5 speedo that provides a modified version of the transducer signal which, on Td5 vehicles, is sent to the engine ECU. I believe the modification is that the frequency is either doubled or halved, alas I can’t remember which. On mine I have used it to feed the cruise control ECU, I’m not sure if it would be suitable for the CUX unit. Quote Link to comment Share on other sites More sharing options...
Ex Member Posted March 14, 2018 Share Posted March 14, 2018 2 hours ago, FridgeFreezer said: You could get massively high-tech and use a transistor fed from the 5v regulated line to pull a 12v line down via a resistor to create a 12v pulsed line. Or if memory serves, the speed signal isn't actually required for the 14CUX to work. The 14CUX uses the VSS signal to determine when the vehicle is stopping and when moving. It has two idle modes for stopped and moving. Without the VSS, the ECU can decide to go into the wrong mode and you tend to stall when coming to a stop or when just sitting idling as the idle control is not aggressive enough. That and you will throw a code, so can't use the CEL. Quote Link to comment Share on other sites More sharing options...
Mo Murphy Posted March 14, 2018 Author Share Posted March 14, 2018 Thanks James. Stephen, I just fancy something new, the 200 has done wonderfully for me and there's nothing wrong with it, just time for a change 😊 Mo 2 Quote Link to comment Share on other sites More sharing options...
Ex Member Posted March 14, 2018 Share Posted March 14, 2018 This is what LR says. Quote Vehicle Speed Sensor (VSS) The Vehicle Speed Sensor is located on the left hand side of the frame on early models, and on the left hand side of the transfer case on later models. It informs the ECM when vehicle speed is above or below 3 mph. This information is used by the ECM to ensure that the idle air control valve (IACV) is moved to a position to prevent a stall when the vehicle comes to a stop. DTC 68 will be displayed if the MAF is greater than 3V at 2000-3000 RPM’s Others state that is also allows for complete fuel cutoff on overrun, which would save a bit of fuel. I've found the stalling issue being a real PITA when the VSS was not connected. Quote Link to comment Share on other sites More sharing options...
Mo Murphy Posted March 14, 2018 Author Share Posted March 14, 2018 Thanks Red90, you are as ever, a fount of knowledge 👍 Mo Quote Link to comment Share on other sites More sharing options...
Ex Member Posted March 14, 2018 Share Posted March 14, 2018 Just spent an excessive amount of time solving this on a friend's truck after doing an EFI conversion. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.