Ok on my 87 k5 the ses light has been comeing on. So i went to check it with the paper clip method and it flashed really fast and went out and won't come on now 
any ideas ?
any ideas ?CK5
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Ses light not working
- Thread starter dheavychevy38
- Start date
Um, that sounds bad. Sure you hit the right pins on the connector?
yup. k5 seem to run fine. When I get home I am going to try to plug in my scanner and see what happens 
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yup. k5 seem to run fine. When I get home I am going to try to plug in my scanner and see what happens
Why'd you paperclip it if you have a scanner?
Hope it ok, good luck.
Scanner at home on laptop and paperclip in tool box at work 
. Well it works with the scanner so I don't know what I did . Still getten the o2 lean code and the est changed code along with no vss reading which is hooked up so not sure whats going on.
. Well it works with the scanner so I don't know what I did . Still getten the o2 lean code and the est changed code along with no vss reading which is hooked up so not sure whats going on.
Does the scanner show vehicle speed when you are moving?
Nope and it didn't before this either.
Does cruise work? How about speedometer? Something up with VSS, if the speedometer works, probably the buffer that is screwed up, or the wiring to it.
No cruise. Speedo does work sometimes from 5 to 25 it will bounce. Any idea what wires i would be looking for ? Still no ses light also.
As for the light, the bulb may have just burnt out on you. Pull the gauge cluster and check/replace the bulb.
No cruise, or scanner reading for MPH is probably a bad VSS module especially since the speedo kind of works. Does the speedo at least read something all the time when you're moving?
No cruise, or scanner reading for MPH is probably a bad VSS module especially since the speedo kind of works. Does the speedo at least read something all the time when you're moving?
Yep, going to have to pull the cluster anyways, test the bulb/wire while its out.
Update So on the way to work today the light came back on which is good and bad . As far as the speedo most days it works fine and others it works it just bounces until over 25 mphs.
which is good and bad . As far as the speedo most days it works fine and others it works it just bounces until over 25 mphs.
If the speedometer works at all, there will be a signal coming from the VSS buffer most likely.
The bulb may be loose in it's socket, or the cluster connector is bad for that circuit. Could be at the ECM connector too, but less likely.
The bulb may be loose in it's socket, or the cluster connector is bad for that circuit. Could be at the ECM connector too, but less likely.
90% of the time the light comes on when slowing down.
What code is the scanner reading? VSS, O2 rich or lean?
I have codes 24. Circuit fault in vehicle speed sensor ,44 o2 lean, and 42 which is est. The truck has new fuel pump,filter and tune up. The light must be back to normal cause it comes on like it did before.
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I'd fix the VSS first, EST is probably tied into vehicle speed (under X vehicle speed, do not use knock sensor) and if the engine is unaware of the load (speed vs. throttle position vs. MAP) fueling might be impacted.
Even if it's not, the VSS/EST codes are probably related. I know for a fact in the TPI PROM's that the knock sensor is disabled under X MPH, so if there is no speed input, it will be "inactive" all the time, which is incorrect of course.
Even if it's not, the VSS/EST codes are probably related. I know for a fact in the TPI PROM's that the knock sensor is disabled under X MPH, so if there is no speed input, it will be "inactive" all the time, which is incorrect of course.
If the speedo is reading mph so i look by the t-case or the speedo for a problem?
On an '87 you need to look behind the speedometer. I would assume VSS is fused, you've checked the fuses?
You can also wiggle the ECM wires around too, since you don't have to pull much, if anything, to access them, to see if its a bad connection. Just easier than pulling the cluster, if you don't have to.
Hint for pulling the cluster, make sure you have slack on the speedometer cable outside the firewall, it makes disconnecting it from the back of the speedometer infinitely easier.
You can also wiggle the ECM wires around too, since you don't have to pull much, if anything, to access them, to see if its a bad connection. Just easier than pulling the cluster, if you don't have to.
Hint for pulling the cluster, make sure you have slack on the speedometer cable outside the firewall, it makes disconnecting it from the back of the speedometer infinitely easier.
fuse nope haven't checked them all yet. Any idea which one is related to the vss ? I will have to check plus i will have to check the wiring cause the po had cut and patched alot of the wiring under the dash between what i would guess was a remote start or alarm and a really crappy radio install 
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nope haven't checked them all yet. Any idea which one is related to the vss ? I will have to check plus i will have to check the wiring cause the po had cut and patched alot of the wiring under the dash between what i would guess was a remote start or alarm and a really crappy radio install .
