help with digital gauge...

[poneyrunner]

ok.. so i have a 1989 240 sx 5 speed car that came originally as a sohc but i converted to a dohc.. everything in the car works perfectly.. i currently have an analog gauge in which works perfectly no problems what so ever with it. well recently i bought a bunch of parts from a guy parting out his 240 with a ca18 motor and one of the pieces was a digital gauge cluster which worked in his car (i tested it and it turned on perfectly). i brought it back tried to install it into my car with my harness and everything worked except for the speedo.. speedo did nothing. so i thought it was my harness so i got one of my buddys to bring me his harness and tried his and same thing everything worked except the speedo. so we tried it in his 89 sohc 240 with both harnesses and they both worked perfectly.. so that is 2 cars in which this gauge cluster worked perfectly but will not work in mine? what could cause that? it tried wiggling my wires a bit while the key on, pushing and holding the mhp/kph knob in, turning the mph/kph knob and anyother knob i cold find with no luck. im lost and none of my friends have any ide about it... thanks for the help.

[poneyrunner]

wow.. no one has ever run into this problem ever? any ideas from anyone? help me figure this out please..

[poneyrunner]

wow.. im amazed.. 46 veiws and no ideas? can anyone possibly look at the fsm and maybe give me an idea at what to maybe start tracing.. I tried looking at it and cant really find anything.. but im also having dificulty understanding it.. please help me i want a digital gauge in my car..

[bb4_96]

is it hud or just digi. Mine had an issue where the speedo plug would come loose. any other issues than that?

[poneyrunner]

just digi gauge.. and none of the wires are loose.. that was the first thing i checked.. then we double checked to make sure it wasnt the different harness.. then we double checked again to make sure it wasnt the cluster.. the digital cluster works perfectly in 2 other cars but the speedo doesnt even seem like its getting power in my car.. everything else on the cluster works perfectly just not the speedo.. and the analog gauge works perfectly..

[TISTO]

its the diffrence between sohc and dual ohc. that's why the guys who swap an sr20 into a sohc car must change the cluster to get it to work, same diff. if you take a cluster out of a ka24de and put it into a ka24e it will not work.

[poneyrunner]

ok.. i have a dohc motor and a dohc cluster.. the onlything about my car that is still sohc is the dash harness... and this cluster worked in a car with a ca18 and my buddies sohc (minus tach for him) so are you saying that i dont have a wire that makes the dohc digital speedo work in my car? i thought the only thing about any of the gauges was the tach.. am i wrong about this? i mean like i said everything on the gauge ie tach, fuel, temp, lights everything except the speedo works on my car.. but in the ca18 everything worked.. and in the sohc everything except the tach worked..

[tabasco122]

Sounds like a grounding issue or something. Do the lights on the cluster come on when in your car?

[KrazyS13]

The dash wiring is the same between SOHC and DOHC as far as the cluster is concerned.. Sounds to me like your speedo died somewhere in between all the cars it's been in... Very common problem with the HUD. Have you kept it on to allow some heat to generate in the cluster?? A lot of times when they start to go out it'll only work after the cluster has warmed up. Sometimes they won't work at all, though..

Have you tried the soldering iron test with the common faulty resistors?? Look around bro, this problem is very common and there are a couple of write ups on the fix.

[poneyrunner]

yes all the lights come on.. the only thing on the cluster that does not work is the speedo.. and i know the cluster is good.. didnt work in my car the first time i tried it so we tried it in my buddies car and it worked flawlessly then with in 30 seconds put it back in my car and it didnt work.. then we put it back in his car to see if it had to do with the hud being hooked up so we left the hud disconnected and it cam on perfectly. and now it currently sits in my car doing the same thing.. everything works except the speedo... its not the cluster.. its something to do with my car..

[inopsey]

you can wire a sohc cluster to work with a sr swap by rewiring the dash harness correctly. sound like thats what you need.