getting pulse instead of steady V to 2-3 solenoid
#1
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getting pulse instead of steady V to 2-3 solenoid
Hi
what can be the matter if i get a pulse to the 2-3 solenoid instead of steady 12V
the valvebody was taken out , and all the solenoids are working like they should after measuting them up and swapping and so on
looks like itīs coming out from the loom
need to measure it all up
i just went threw conversion swapp M6 to Auto and needed to install a jumper harness from RPM and Reflashed the PCM to Auto
but i donīt think i swapped wires wrong because when i press threw scanner to the 2-3 solenoid it reacts just rattles instead of one click
could this be some issue in the PCM
wouls somebody share some light to this
thanks
Baezi
what can be the matter if i get a pulse to the 2-3 solenoid instead of steady 12V
the valvebody was taken out , and all the solenoids are working like they should after measuting them up and swapping and so on
looks like itīs coming out from the loom
need to measure it all up
i just went threw conversion swapp M6 to Auto and needed to install a jumper harness from RPM and Reflashed the PCM to Auto
but i donīt think i swapped wires wrong because when i press threw scanner to the 2-3 solenoid it reacts just rattles instead of one click
could this be some issue in the PCM
wouls somebody share some light to this
thanks
Baezi
#2
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Are you referring to the shift solenoid or perhaps you meant the 3-2 solenoid? The 3-2 is a PWM (pulse) solenoid.
The shift solenoids are best referred to as just A and B since the 4 different on/off combinations give you the 4 gears.
(Not to be insulting, but the shift solenoids are right next to each other.)
Now, if one of the shift solenoids is receiving pulses, then this sounds like a mixup in the wiring harness.
The shift solenoids are best referred to as just A and B since the 4 different on/off combinations give you the 4 gears.
(Not to be insulting, but the shift solenoids are right next to each other.)
Now, if one of the shift solenoids is receiving pulses, then this sounds like a mixup in the wiring harness.
#3
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Are you referring to the shift solenoid or perhaps you meant the 3-2 solenoid? The 3-2 is a PWM (pulse) solenoid.
The shift solenoids are best referred to as just A and B since the 4 different on/off combinations give you the 4 gears.
(Not to be insulting, but the shift solenoids are right next to each other.)
Now, if one of the shift solenoids is receiving pulses, then this sounds like a mixup in the wiring harness.
The shift solenoids are best referred to as just A and B since the 4 different on/off combinations give you the 4 gears.
(Not to be insulting, but the shift solenoids are right next to each other.)
Now, if one of the shift solenoids is receiving pulses, then this sounds like a mixup in the wiring harness.
seemes as 2-3 shift solenoid is recieving pulse (rattles)
and the car is like it is stucked in two gears when in 1st gear
maby itīs in 1 and 4
Baezi
#4
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I have not "scoped" all the 4L60E lines, but I wonder why the 3-2 shift solenoid would even get pulses except during a downshift. So, even if the wiring was mixed up, this makes no sense.
Still, I would start by double checking the wiring harness again. Note that the PCM wiring for Corvettes is often a bit different than for other cars.
Still, I would start by double checking the wiring harness again. Note that the PCM wiring for Corvettes is often a bit different than for other cars.
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I have not "scoped" all the 4L60E lines, but I wonder why the 3-2 shift solenoid would even get pulses except during a downshift. So, even if the wiring was mixed up, this makes no sense.
Still, I would start by double checking the wiring harness again. Note that the PCM wiring for Corvettes is often a bit different than for other cars.
Still, I would start by double checking the wiring harness again. Note that the PCM wiring for Corvettes is often a bit different than for other cars.
i only had time to looke at the pcm connections and harness last night and nothing seemed to be mixed. in the carīs harness.
what i think is strange the transmission guy said that the 2-3 solenoid was rattling but what i found out when i was manual pressing the solenoids in the HPT scanner whith the switch power on
1-2 shift : rattles
1st : rattles
2nd: rattles
2-3: ok
3th: ok
4th :ok
TCC PWM: ok
TCC solenoid: nothing
this will be horror to find out
so where in the hell is the tranny getting the pulse for this solenoid, makes me think my PCM is maby fucked.
does pin 20 PuRle wire in green/red connector Signal low -front have
something to do whith the trans i saw that wire was compressed and shot need to fix it.
Baezi
#6
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I reviewed the 2003 Corvette PCM wiring diagrams. I have no idea what "Signal Low - Front" and "Signal High - Front" are. Really don't think they have anything to do with the trans.
I assume you know that the Shift solenoids are on Pins 47 (Yellow/Black) and 48 (Light Green) of the PCM's RED connector.
My guess is that the PCM does not have the "oomph" to pull down the Solenoid's ground line (i.e. complete the circuit). It pulls it down, releases it, pulls it back down, etc, giving the "rattle".
Since you have HP Tuners, here is what I would do:
1. Drop the pan and confirm the "rattle" when selecting 1st gear.
2. Swap the solenoids to see if you have the same rattle.
If the rattle is now different, e.g. when selecting 3rd gear, then one of the solenoids is defective; replace both.
Otherwise, you might indeed have a problem with the PCM.
I assume you know that the Shift solenoids are on Pins 47 (Yellow/Black) and 48 (Light Green) of the PCM's RED connector.
My guess is that the PCM does not have the "oomph" to pull down the Solenoid's ground line (i.e. complete the circuit). It pulls it down, releases it, pulls it back down, etc, giving the "rattle".
Since you have HP Tuners, here is what I would do:
1. Drop the pan and confirm the "rattle" when selecting 1st gear.
2. Swap the solenoids to see if you have the same rattle.
If the rattle is now different, e.g. when selecting 3rd gear, then one of the solenoids is defective; replace both.
Otherwise, you might indeed have a problem with the PCM.
#7
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I reviewed the 2003 Corvette PCM wiring diagrams. I have no idea what "Signal Low - Front" and "Signal High - Front" are. Really don't think they have anything to do with the trans.
I assume you know that the Shift solenoids are on Pins 47 (Yellow/Black) and 48 (Light Green) of the PCM's RED connector.
My guess is that the PCM does not have the "oomph" to pull down the Solenoid's ground line (i.e. complete the circuit). It pulls it down, releases it, pulls it back down, etc, giving the "rattle".
Since you have HP Tuners, here is what I would do:
1. Drop the pan and confirm the "rattle" when selecting 1st gear.
2. Swap the solenoids to see if you have the same rattle.
If the rattle is now different, e.g. when selecting 3rd gear, then one of the solenoids is defective; replace both.
Otherwise, you might indeed have a problem with the PCM.
I assume you know that the Shift solenoids are on Pins 47 (Yellow/Black) and 48 (Light Green) of the PCM's RED connector.
My guess is that the PCM does not have the "oomph" to pull down the Solenoid's ground line (i.e. complete the circuit). It pulls it down, releases it, pulls it back down, etc, giving the "rattle".
Since you have HP Tuners, here is what I would do:
1. Drop the pan and confirm the "rattle" when selecting 1st gear.
2. Swap the solenoids to see if you have the same rattle.
If the rattle is now different, e.g. when selecting 3rd gear, then one of the solenoids is defective; replace both.
Otherwise, you might indeed have a problem with the PCM.
seemes as the problem does not lie in one of the solenoid they all work correctly and also tried swapping them
looks as the the problem comes from the loom
thanks
Baezi
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#8
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Ok, here is what I would do next.
I would put a volt meter (or oscilloscope if you have access to one) on the solenoid to confirm that the ground side is pulsing.
I would then check pin 48(?) of the PCM Red connector to verify the same voltage pulses.
If you also have voltage pulses on the PCM, then I think the PCM is defective.
If no voltage pulses on the PCM (e.g. reads close to 0 volts steady), then you have a bad connection or broken wire between the PCM and the solenoid.
You can read the voltage of a PCM pin by pushing a thin needle into the connector next to the wire, or even into the wire. Personally, I push one end of a 1K resistor into the connector and then measure at the other end. The 1k resistor will have no effect on voltage measurements and will prevent PCM damage if you accidentally short something out.
I would put a volt meter (or oscilloscope if you have access to one) on the solenoid to confirm that the ground side is pulsing.
I would then check pin 48(?) of the PCM Red connector to verify the same voltage pulses.
If you also have voltage pulses on the PCM, then I think the PCM is defective.
If no voltage pulses on the PCM (e.g. reads close to 0 volts steady), then you have a bad connection or broken wire between the PCM and the solenoid.
You can read the voltage of a PCM pin by pushing a thin needle into the connector next to the wire, or even into the wire. Personally, I push one end of a 1K resistor into the connector and then measure at the other end. The 1k resistor will have no effect on voltage measurements and will prevent PCM damage if you accidentally short something out.
#9
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Ok, here is what I would do next.
I would put a volt meter (or oscilloscope if you have access to one) on the solenoid to confirm that the ground side is pulsing.
I would then check pin 48(?) of the PCM Red connector to verify the same voltage pulses.
If you also have voltage pulses on the PCM, then I think the PCM is defective.
If no voltage pulses on the PCM (e.g. reads close to 0 volts steady), then you have a bad connection or broken wire between the PCM and the solenoid.
You can read the voltage of a PCM pin by pushing a thin needle into the connector next to the wire, or even into the wire. Personally, I push one end of a 1K resistor into the connector and then measure at the other end. The 1k resistor will have no effect on voltage measurements and will prevent PCM damage if you accidentally short something out.
I would put a volt meter (or oscilloscope if you have access to one) on the solenoid to confirm that the ground side is pulsing.
I would then check pin 48(?) of the PCM Red connector to verify the same voltage pulses.
If you also have voltage pulses on the PCM, then I think the PCM is defective.
If no voltage pulses on the PCM (e.g. reads close to 0 volts steady), then you have a bad connection or broken wire between the PCM and the solenoid.
You can read the voltage of a PCM pin by pushing a thin needle into the connector next to the wire, or even into the wire. Personally, I push one end of a 1K resistor into the connector and then measure at the other end. The 1k resistor will have no effect on voltage measurements and will prevent PCM damage if you accidentally short something out.
thanks man
Baezi
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iīm gona measure all plugs and wires from PCM to solenoids in the Auto
but not sure what to looke for
or if you donīt understand me i mean if i measure 1-2 shift solenoid am i looking for voltage or ground when i manual press the solenoid in HPT for example.
i have i draws of the plugs and wires and what colour they are just need to know what to looke for
thanks
Baezi
but not sure what to looke for
or if you donīt understand me i mean if i measure 1-2 shift solenoid am i looking for voltage or ground when i manual press the solenoid in HPT for example.
i have i draws of the plugs and wires and what colour they are just need to know what to looke for
thanks
Baezi
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my trouble was in the tune
the Reflash medhod was wrong, we only did change the current MN6 tune into Auto but that doesnt work
i had to write complete new tune in , a stock Auto tune whith an other Vin and all
works great now....
Baezi
the Reflash medhod was wrong, we only did change the current MN6 tune into Auto but that doesnt work
i had to write complete new tune in , a stock Auto tune whith an other Vin and all
works great now....
Baezi