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OBDI Code 49 Service throttle soon circuit fault

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pronghorntractorworks

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I got a service throttle soon circuit fault on gmtdscan tech. My 94 k3500 crew cab does not have a STS light in the cluster. WTF? I am having some timing issues and I have read you cannot set tdc learn and offset with trouble codes... thanks
 
does the code come back instantly when you clear it? if not you might have a big enough window of time to do TDCO.
 
Those Grounds at the back of the engine (last intake stud and Tranny dipstick stud) have set my STS and SES lights on.

R and R.....Can't hurt and it's free.
 
If the sts light is not coming on then the bulb is more than likely burnt out which will cause the circuit code. pull the cluster and check the bulb before driving yourself crazy with it.
 
Yukon, the cluster does not have a slot for an STS light. AK, the code comes back instantly. Louis, i cleaned the one on the back of the pass head. I did not know there was one on the dipstick. I will check it tomorrow.
 
The grounds have been cleaned. The braided ones are attached to the frame on the passenger side. From there, one goes down to the bellhousing by the starter, and the other goes up to the firewall just below the heater core pipes. Unfortunately they did not solve my code 49....:banghead:
 
1995yukon65 said:
If the sts light is not coming on then the bulb is more than likely burnt out which will cause the circuit code. pull the cluster and check the bulb before driving yourself crazy with it.
Click to expand...

:hammer:

pronghorntractorworks said:
Yukon, the cluster does not have a slot for an STS light. AK, the code comes back instantly. Louis, i cleaned the one on the back of the pass head. I did not know there was one on the dipstick. I will check it tomorrow.
Click to expand...

DTC 49 - Service Throttle Soon Lamp Circuit Fault

Computer is saying it doesn't see a ground path to turn this lamp on. So the lamp is out, bad wire to the lamp, or you have the wrong cluster. Does the fuel gauge say "diesel fuel only?" as someone may have dropped a gas cluster in. Otherwise you may be overlooking the spot for the STS light that isn't working. Also possible they dropped in a diesel cluster from a 1993 that has mechanical injection and no STS.
 
just an update on this. Warwagon was dead-on. The cluster was from a 93.... makes me wonder how many miles are REALLY on the truck. can't be too many since the truck is not fudmucked. I got some bulbs and stuck them in every spot in the cluster. no more code 49. not sure which slot it is. might try to find it when i have time. not soon though. anybody have a photo of where the light is located on a 94?
 
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