(blacktop SR20det) Gauge cluster help!

[hwy1]

My tachometer and speedometer both don't work .

I beleve that whomever did the swap didn't change the speed sensor on the transmission or it's broken. is there a way to test volts or something to eliminate that possibility?

also, It's a 1990 240sx, so i swapped out the tach for a stock SR tach from a jdm cluster. no luck. i put the tach back in the Jdm cluster and plugged that in and it still doesn't work. all of the lights, gas gauge and temp gauge work just fine.

My friend was using the jdm cluster in his 1990 240sx with a redtop sr20det with no problems.

Any ideas?thanks
Modified by hwy1 at 11:28 PM 4/26/2007

[SpeedRacer1]

Sounds like wiring problems. If it is an S13 blacktop then you do not need to change the speed sensor with the KA. Follow the circuits to see if they got cut somewhere.

[Hijacker]

also check your under dash wiring. there's a white plug that the ECU connects to going up into the dash.

[hwy1]

is there a way to test if the gauges are broken?

Modified by hwy1 at 5:46 PM 4/27/2007
Modified by hwy1 at 3:40 PM 4/28/2007

[hwy1]

the tach is getting 13.8 volts and the other wire (yellow/red stripe) going from the sr harness to under the dash is reading at 6.6 - 6.8 volts.

I tried running a wire from the yellow/red directly to the back of the tach and still nothing.

has anyone had this problem? could it be a problem with the ECU?

[drftsx]

im in the same boat. i had a sohc speed sensor on it but tach doesnt work at all rpm does though. oh yeah i also had a jdm cluster redline 7500rpm. If you figure it out let me know. im about to move the engine into my other s13.

[Sr20Det20]

ok guys 2 solve ur problem 90 91 the tach does not work for sr swaps its 92 and uo so jus go 2 a junk yard get a 92 or 93 tach and install fits right in it will work

[SpeedRacer1]

ok guys 2 solve ur problem 90 91 the tach does not work for sr swaps its 92 and uo so jus go 2 a junk yard get a 92 or 93 tach and install fits right in it will work

You didnt read any of his post did you? He said he has a 1990 240SX and swapped out the 1990 tach for a JDM SR20DET tach.

And its not 1990-1991 that doesnt work for SR swaps, it is 1989-1990 KA24E tachs.

[drftsx]

i have also a 91 s13 so ill try its speed sensor on it to see if itll work.

[hwy1]

Question to all that have this same problem. Is your your speedometer also not working? mine doesn't work right now and I just thinking, maybe if the speed sensor isn't working correctly, the ECU may send off a bad tach signal. Can someone confirm that?
Modified by hwy1 at 6:25 PM 4/30/2007

[BRADYNS240SX]

i have the same problem only with a redtop wondering if blacktop and redtop would be the same if not does anyone know how to fix the problemthanks

[nothix]

Question to all that have this same problem. Is your your speedometer also not working? mine doesn't work right now and I just thinking, maybe if the speed sensor isn't working correctly, the ECU may send off a bad tach signal. Can someone confirm that?

Modified by hwy1 at 6:25 PM 4/30/2007

sorry for the old bump, but didn't want to start a new thread.

Has anyone proved/disproved this?

I CANNOT get my tach to work.

The car is an 89, SR20DET Blacktop. Everything else works, but speedo is pretty iffy. Bounces around and sometimes reads really wrong (100+ mph).

I have a DOHC cluster installed. Performs exactly the same as a SOHC cluster. Everything works but Tach.

I found that the yellow/green wire was cut from my ecu, which is speed sensor output. Connecting this wire with the other end off of the cluster plug, yielded no results.

I've checked continuity between the yellow/red wire leaving the ecu and the yellow/red wire connecting to the dash plug, from the dash plug to the back of the cluster, and from the ecu to the dash. They all ohm out.

One thing I've noticed is that I'm getting 3v at idle on the yellow/red tach wire, and it drops so 2.6 with light throttle. It appears that the more throttle, the lower the voltage. Does this seem correct?

I've spent over 10 hours, checking all the wires, swapping clusters, trying aftermarket gauges, nothing can get that tach to move a bit.

Thanks for any help at all anyone can provide. I've to an end with ideas.-nothix