Alright I just got my 240sx and the speedomoter and odo don't work. Someone told me it could be a pcm but I don't think the 240 even has one. What I narrowed it down to was the speed sensor in the transmission. Now does anyone know if it could be something else? cause I don't want to be replacing a $130 sensor unless I know for a fact its whats wrong. Thanks!

 

replace your 10amp electronics fuse. if that doesnt fix it.. then yea its the sensor. which is mechanical...

 

is your car lowered?

 

ahaaaha that too

 

generally speaking, pcm is just a way of referring to both the ecu and tcu. although i've heard some refer to the ecu as the pcm when talking about fords specifically. so yes, your car does have a pcm.

but first define, "don't work" mine both work but the odometer will indicate have a mile or so traveled when the car is parked and idling. then the speedometer will read 15 miles over or nothing 25 miles under at time. mine work, but they are far from accurate.

 

I believe it's lowered some. And the speedo and odo and trip don't work. at all they are completely dead. I looked and non of the fuses refer to anything with the speedo.. But I guess I'll pull every one and take a look.

 

the speedo is based under electonics

 

check under your driver side if not the passenger side front fender and see if your wiring harness is okay

 

okay I looked in the fuse panal under the dash and I found the electronics fuse and it should be the very last one on the left side. well there was no fuse there. I put a fuse in there and went for a drive but it still didn't work. so i think its my speed sensor.

 

I checked the wiring harness and it looked fine. no wires were broken or ripped out.

 

Check any nearby junk yards to see if they may have one or shop around online. Someone will be parting out their car more than likely. Probably cheaper than buying new.

 

I have 2 240's where the odometer seems to be broken. When i didi the ecu diagnostics it throws the code for the speed sensor. more than likely that is the problem you are having. It is very common with our 240's, and less common with 300z's which use a manual flex wire rather than an electronic signal that the 240's use.

 

my speedometer just started flying all over the place. it will slowly to up all the way, then work its way back down or maybe work for awhile. I already changed the sensor, but that didn't help. I couldn't find a post with this problem. Any ideas out there?

 

could be the cluster.
my speedo used to be bouncy and then eventually died and then my ecu thru a code for the speed sensor.
before i checked the speed sensor i swapped my SE cluster for a base model cluster with LEDs and the speedo is perfect.
i was bummed about having to buy another speed sensor when the ecu gave me that code, but i guess it was the cluster that was bad.