Hey guys,

I have a 1993 Rev2 JDM 3SGTE in a 1986 N/A Canadian car.

Ive been having an issue with my car giving code:42 "No SPD signal for 8 seconds when engine speed is between 2,500 rpm and 5,000 rpm and coolant temp is below 80C except when racing the engine." even though I have a mechanical speedo sensor installed.

The speedo sensor I installed has only a mechanical output. It does not have an electrical output like the one below (which has both), but I was told this was not a problem and that I can just hang the plug in the bay.


I double checked my wiring and the connections are good.


From my understanding the ECU gets a signal from a sensor at the Gauge Cluster that tells it how fast the car is going. To test whether I was getting a signal from the cluster I put my car onto jack stands, started it up, put it into first, clicked the e-brake a couple of times to slow it down to a crawling speed, and then connected a multimeter to the purple/white wire at the ECU to see if there was a signal. It was receiving a constant 4.5volts. From my understanding it should be a pulsating signal, but my multimeter is probably too slow to recognize the pulse. Either way, there is a signal being sent from the dash gauge cluster.


Ok, so after all of that, I have NO CLUE what to do next. Why am I still getting a code 42?
My next test is to remove the speedo cable and turn it by hand and do the same test with the multimeter, then I may be able to slow it down further than by running the car in first.

Hopefully somebody here knows whats going on. I shouldnt need the speedo sensor with the electrical pigtail, should I?