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this is for a 84 A150 style colt, anyone know or have a gauge cluster wiring schematic to see if it has a reed switch/vss. i need a speed sensor signal to get the dsmlink properly tuned.
i ordered a haynes manual from my libarary, but they cant find it on the self and i don't want to spend $25 just to see a gauge cluster wiring schematic if i buy/order one new from my local parts store.
thanks

The speedometer is a cable driven device, not electrical. There is a cable that connects to the transmission and tranfers motion to the speedometer in the gauge cluster. I see no way to get a speed signal from the guage.

The book says that it is an "electromagnetic induction system rotating pointer type"

I can tell you that the book indicates that the gauge will read 60 mph with the cable rotating at 1,026 rpm.

Sorry.

yes i understand that, all 1g's and i assume most csm's are cable drivin. but theres a reed switch in the cluster to tell the ecu how fast the car is moving for long and short term fuel trims. iam wondering if the 84 cluster has this reed switch.
if not, my options are swapping a 1g cluster in, a later csm cluster or using a 2g vss which takes place of the cable but i'll lose my speedo all together.

I've always been told that the ECU in a 1g/CSM has no idea how fast the car is going, it just knows that it's moving or not moving. I was also told that fuel trims work off Karman Hz to determine low and medium fuel trims.

well you have been told wrong as far as 1g's go, like i said iam not 100% positive on csm's, but i do know a few csm's running dsmlink, so i assume the later csm's have a reed switch also.
dsmlink must make the mph up as the revs climb
the ecu knows the speed because of the reed switch in the cluster..............

i have the colt running on dsmlink, but without a vss(reed switch) signal to the 1g ecu, i can't tune the long term fuel trims, use the launch control, no lift to shift or the nitrous controls if i need to.

That's very strange. I've always used the clutch switch method for the stutter box on my cars using the speed sensor. You would think if a 1g knew how fast it was going there would be a way to datalog it using a pocket logger or similar, but you can't. I've talked to several people on the DSM ECU mailing list who have verified this also, so hearing about this is a first for me.

Since a CSM will run on a 1g DSM ECU with no problems, I have to assume it functions the same way with regard to the speed sensor.

well since i dont have a clutch switch in my car, i cant use the clutch switch to turn off the stutter box, i have to rely on the speed sensor to do it, untill i figure out how iam mounting a clutch switch in this car. so unless the dsmlink reads a speed greater then 0, my stutter box is always on. and yes, i need the output from my cluster's reed switch if it has one, which is my original question, and run a wire from the reed switch to my ecu.
and if you buck up and buy something alittle more user friendly then a pocket logger and SAFC, you can log all this and tune till you can't tune no more
http://www.ecmtuning.com/wiki/dsmlinkloggableparams
notice Speed is loggable in dsmlink, so tell alll your friends on the ecu mailing list to buy dsmlink if they want to really log and tune correctly

Yeah, on a 2g. I don't see anything that says it's loggable on a 1g. Even using mmCd to log, which is much better than the pocket logger software, you cannot log speed. I guess I will just drop everything and get ECMLink now. Shit, does it have an output to turn on my coffee pot once I hit 15lbs. of boost?

that is a 1g and 2g loggable list, i think the 2g has a rear o2 sensor and one other sensor that a 1g dosen't.

i guess some people can't admit when there wrong
and yes you could turn on a coffee pot when you hit 15 pounds of boost through a relay or 2 with dsmlink

I have zero problem admitting when I'm wrong, I just like to see proof first.

pm your email address, and i'll send a bunch of dsmlink logs from my 1g and now my colt, and you can post them here for everyone to see.

but back ontopic, i ordered a shop manual for my 84 colt, so i guess i will know shortly if it has a reed switch or not.

I used to own an 84 turbo that would set an error code for speed sensor. I have the factory manual in front of me and I can't find it. The book shows an error code listed for bad speed sensor but I can't find it in the wiring diagram. It could be there somewhere, very small print. Greg

thats good news, iam sure its in the cluster i hope........
thanks

I really don't have a great answer, but at least the dsmlink ecu(which functions as a stock ecu) does read speed. The reed switch does get a signal to the ecu. I am no tentirely familiar with how it works, but I assure you, you will run into issues on a 1G ecu if the speedometer cable is unhooked. And even worse issues on a 2G.

There is a little trick on a 1G that you can get away with though. You can NOT run a cable and the car will perform. You just set your launch rpm to what ever your rev limit is, and all is well. You will just have poor launch control.

On a 2G however, the car will go into limp mode and there will be a bunch of issues as this doe suse a TRUE speed sensor.