throwing code 636-2 engine sputtering while active. does not do it all the time. Followed diagnostic procedure for speed/timing test and everything checked good. Last step of the procedure is checking the pulsar gear torque spec which I didn't do because it would require pulling the engine. At the end of the procedure it states to contact tech support is issue was not resolved. Does anyone have experience with this code and know what the next step might be.
Based on previous experience on this forum the first suspect is a faulty engine wiring harness that is probably partially rubbed through somewhere. Have you carried out a thorough inspection of the harness yet.? The places to concentrate on are anywhere that the harness is pulled tight around a corner by supporting brackets and any support where the harness is being squeezed by zip ties. Do you have an electrical schematic.? See this link HeavyEquipmentForums
Yes I have a schematic and will inspect the harness and see what I find. Is it possible to ohm out the the wiring since this has the resistor in the harness? If it is can you help me find the correct corresponding pins to test.
Ohming the wiring is Cat’s recommended test method but it has a drawback. That is if a wire is almost worn through but still has a few strands intact it will show as “good” on a resistance test. Yet ask it to pass operating current or a clean signal from a sensor and it will either break down completely or screw up the signal. I generally suggest to disconnect main harness and ECM connectors then test wires one at a time using a fused 5A test light supplied with batt+ connected to one end of the wire. Jumper the other end to machine frame ground. Any wire that will pass 5A can be regarded as good.
I will do that thank you. Once I find where the issue is I will post the results.
If I were to run overlays do you know how the resistor in the circuit be wired in?
Doesn't the electrical schematic show both the wires connected to it and also the location.? As a matter of interest what is the Cat Publication reference you are using for a schematic.?
findings after testing circuits with 5a test light. signal *J2 pin 29 OR 997 to resistor pin A OR 997 tested good *J2 pin 29 OR 997 to sensor pin 1 OR 997 tested good *(resistor pin A OR 997 to sensor pin 1 OR 997 did not light test light) 5V *J2 pin 68 PU Y733 to resistor pin B PU Y733 tested good J2 pin 68 PU y733 to sensor pin 3 PU y733 tested good resistor pin B PU y733 to sensor pin 3 PU y733 tested good ground J2 pin 6 YL 993 to sensor pin 2 YL 993 tested good
Going to run an overlay fron J2 pin 29 to the resistor and the sensor
Scratch that I found the broken section of the wire going to repair that area. the break was right where the 2 wire plug for the resistor comes out of the main harness where it is mounted to the rear tab below the fuel rail. Hope this helps someone.
Good to hear. Please post some photos of the damage if you can.