No speed indication on both speedo & Power FC

[Mikester]

As stated in the subject line. I got no speed indication on the speedo and the Power FC reads zero the whole time as well.

The car is a 1992 auto to manual swap w/SR. Wiring Specialties upper & lower harnesses.

I went here (http://site.wiringspecialties.com/Wholesale_Instructions/S13SwapTransmissionHarness.pdf) and verified everything was hooked up properly for auto to manual swap with respect to the speed sensor- found I had the manual/auto to manual conversion plug mixed up; so I put the correct plug in... no fix.

Then I swapped in a known good speed sensor- no fix.

So here I sit. Before I go tearing into wiring diagrams etc; I wonder if maybe any of you guys have had & solved the same or a similar issue. Could it be something as stupid as a connector not connected behind the cluster? I feel like something isn't connected that should be and without looking in the books; I am stumped as to what it could be...

BTW- The speed indication was fine with the KA... and other than the lack of speed indication with the SR; the car runs like a wet dream.

Thanks in advance.

Mike

[Mikester]

Well, the only thing I've done differently besides put in my Okinawa transmission was install the Nismo speedo... Quadruple checked all the connections everywhere else- all good; so I guess it's time to pull the cluster back out & check there.

Damn.

[fliprayzin240sx]

Have you checked with Yury for troubleshooting tips? He should have some ideas. My guess is wiring related since the ECU isnt seeing it too. I'd chase that Yellow/Green wire to see where the disconnect is.

[Mikester]

^^Ray, according to the diagrams, it's like many other cars where the VSS signal goes thru the speedo prior to the ECU. Gonna have to pull the cluster & check that the speedo is installed correctly and/or wired for Chuki 180SX...

[silnv]

I just did an auto to manual in my coupe last week. Put in a SR at the same time. I didn't have any signal at the speedo either, also my alternator was not charging. After some troubleshooting, I found using the manual sr alt/starter harness was my problem, the chassis harness on the auto has a 4 pin plug, two for speed sensor, one for alt signal, one for oil pressure. I took the alt/starter harness from my auto tranny ka and hooked it up, it took care of both my problems.

[jr_ss]

Mike, the speedo is polar, so having the wires switched will cause your speedo to read incorrectly or not at all. A quick check would be to put two jumper leads in on the opposite wire they would be attached to with the plug mated.

[Mikester]

I just did an auto to manual in my coupe last week. Put in a SR at the same time. I didn't have any signal at the speedo either, also my alternator was not charging. After some troubleshooting, I found using the manual sr alt/starter harness was my problem, the chassis harness on the auto has a 4 pin plug, two for speed sensor, one for alt signal, one for oil pressure. I took the alt/starter harness from my auto tranny ka and hooked it up, it took care of both my problems.

I know what you're talking about... I wonder if your car is an 89, 90 or 91... The 92' auto manual swap is slightly different; and I verified all my connections at the lower harness are where they should be. My alternator, oil pressure, and everything else is working as advertised- Just the speedo is inop. I changed the 180SX speedo to the Nismo during the swap- having verified everything else is hooked up; I will start there.

Mike, the speedo is polar, so having the wires switched will cause your speedo to read incorrectly or not at all. A quick check would be to put two jumper leads in on the opposite wire they would be attached to with the plug mated.

Hmm... interesting, but makes perfect sense (hence why speed always reads 0 in reverse lol). Will definitely check that when I get the cluster out. Not sure if it's possible to have hooked the little connector back there upside down, but stranger things have indeed happened ;)

Kids are out for summer... so time is at a premium atm- Once I get the cluster out & do some testing, I will report back.

Thank you everybody so far for the help/inputs~

Mike

[jr_ss]

You can perform my test at the connector for the speed sensor without having to pull the cluster out FYI.

[Mikester]

:facepalm:

Oh yea lmao! That whole 'smarter not harder' thing gets me once in a while...

Are the connectors pretty easy to de-pin without breaking them? If so, I could just swap the VSS leads right at the connector vs. jumper them.

[jr_ss]

Yeah, they aren't super hard to depin, ask me how I know...

[Mikester]

^^I tried depinning my spare VSS yesterday... Decided to go another route using male/female bullet connectors... If it DOES work, I would still like to be able to easily switch back to the std signal down the road. Heading down to do it... will let y'all know.

[fliprayzin240sx]

You hit up Yury to see if he got any other idea?

[jr_ss]

You hit up Yury to see if he got any other idea?

Most likely it is just a mispinned wire. It's a pretty basic signal system.

[Mikester]

^^Sorry this has been a while... Kids are out for summer and they rule my world when they are here... Going down in a few min to switch the polarity of the VSS signal. If that doesn't work, I am going to try my 'known-good' 180SX speedo before breaking out the meter and/or calling Yuri.

[Mikester]

Update:

Switched VSS polarity... No dice. Gonna put the 180SX speedo back in. If that doesn't work, then I will be getting a hold of Yuri and chasing sparks.

[jr_ss]

Damn... Well it was worth a shot. I had to get on the horn with Dakota Digital when mine wouldn't work to figure out the issue.

[Mikester]

Damn... Well it was worth a shot. I had to get on the horn with Dakota Digital when mine wouldn't work to figure out the issue.


Yup- nothing lost there lol....

If the 180SX speedo works- No worries... Will just hold onto the Nismo and figure out what the issue is.

Update to come~

[Mikester]

Put the 180sx speedo back in & switched the wires back. Still no speed indication. Gonna call Yuri tomorrow.

[Mikester]

OKAY, now we are getting somewhere...

Called & talked to Yury... It seems that with auto/manual swaps like mine, WS has not been able to rope down an exact formula by VIN with respect to the 7-pin and 4-pin style connectors... As it turns out, the 7-pin connector at the top left of the pic is supposed to connect to the 4-pin connector mounted to the fuse box at the top of the pic:

http://farm6.staticflickr.com/5513/9161537646_a81b387e18_b_d.jpg

I also examined the Nismo speedo when I had it out & the circuitry appears to be the exact same as the 180SX with nothing visibly cooked...

Weird thing is that Yury also said my oil pressure & alternator charge run thru these connectors... but I've driven the car at LEAST 300-400mi seating the rings and have yet to have any charging or oil pressure-related issues. I just sent off an email and Yury said the connector I need to join them will go out in the mail on Monday. Bad news is that I will prolly have to take the damned dash apart again :(

However, I suppose a JDM tyte speed speedo is worth twice the trouble ;)

Will update with the fix (fingers crossed) soon.

Thanks everyone for the inputs so far~

Mike

[e1_griego]

Auto car require auto lower harness as the chassis-side wiring is different between cars.

5spd lower harness in auto car ended up having the alternator kick out 15+v in my car, and ended up frying the alternator and a couple other things.

Plus the speedo didn't work.

[Mikester]

^^Thanks, but I have a Wiring Specialties lower harness as well, which accommodates auto to manual swaps (stated in 1st post) ;)

[e1_griego]

^^Thanks, but I have a Wiring Specialties lower harness as well, which accommodates auto to manual swaps (stated in 1st post) ;)

clearly not working for you ;)

I would just throw the auto harness back in and call it, since it works.

Either way, sounds like it's taken care of.

[Mikester]

As stated 'again' it's a hit/miss thing with the WS harnesses with respect to those 2 plug styles... The previous harness 'worked' but was about as ghetto as you could ever imagine (hacked all to shit, greasy as hell, horrible terminals/splices; no reverse lights etc). If you've seen my build and/or my engine bay, you'd see real quick why anything other than clean functional and quality bits will never be associated with my car ;)

[e1_griego]

No need to dick swing to me, I know you have a clean engine bay.

If you've seen my car, I like things that work haha.

I didn't realize there was a difference between auto harnesses through the years, so I suppose that's good to know.

[Mikester]

^^Right, it's weird. I knew that there were differences between the SOHC & DOHC auto/man setups, but not differences within the same year group/type. Hopefully water under the bridge in due time.