4L80E no lockup issue
Thread Starter
Teching In
Joined: Jan 2009
Posts: 37
Likes: 2
From: Ionia, Michigan
4L80E no lockup issue Fresh rebuild, in a C10 behind a LQ4. Florida Converters 3400 rpm stall. P59, DBW.
Tune never commands lockup.
If I command it via HPT Scanner, it shows "on" but no rpm drop, doesn't seem to be on.
What troubleshooting steps should I follow to run this down?
Tune never commands lockup.
If I command it via HPT Scanner, it shows "on" but no rpm drop, doesn't seem to be on.
What troubleshooting steps should I follow to run this down?
On The Tree
Joined: Sep 2018
Posts: 161
Likes: 4
From: New Zealand
Sounds like two seperate issues:
1. Why is computer not commanding lockup? Possible causes include shitty tune, faulty brake switch, engine misfire, engine/trans overtemp, certain trouble codes etc etc
2. Why is lockup not engaging when commanded manually? Possible causes include warn TCC regulator valve, failed or leaking PWM solenoid, failed or leaking TCC Apply solenoid, paralyzed TCC Apply valve in pump. Pull the pan and remove both pwm and tcc apply solenoids. Command them on with scan tool and see if they 'click' and hold pressure. Check them for cracks. Use the pick to actuate the apply valve and see if it moves freely in its bore.
Getting trans pressure readings could be helpful also.
1. Why is computer not commanding lockup? Possible causes include shitty tune, faulty brake switch, engine misfire, engine/trans overtemp, certain trouble codes etc etc
2. Why is lockup not engaging when commanded manually? Possible causes include warn TCC regulator valve, failed or leaking PWM solenoid, failed or leaking TCC Apply solenoid, paralyzed TCC Apply valve in pump. Pull the pan and remove both pwm and tcc apply solenoids. Command them on with scan tool and see if they 'click' and hold pressure. Check them for cracks. Use the pick to actuate the apply valve and see if it moves freely in its bore.
Getting trans pressure readings could be helpful also.
Thread Starter
Teching In
Joined: Jan 2009
Posts: 37
Likes: 2
From: Ionia, Michigan
Sounds like two seperate issues:
1. Why is computer not commanding lockup? Possible causes include shitty tune, faulty brake switch, engine misfire, engine/trans overtemp, certain trouble codes etc etc
2. Why is lockup not engaging when commanded manually? Possible causes include warn TCC regulator valve, failed or leaking PWM solenoid, failed or leaking TCC Apply solenoid, paralyzed TCC Apply valve in pump. Pull the pan and remove both pwm and tcc apply solenoids. Command them on with scan tool and see if they 'click' and hold pressure. Check them for cracks. Use the pick to actuate the apply valve and see if it moves freely in its bore.
Getting trans pressure readings could be helpful also.
1. Why is computer not commanding lockup? Possible causes include shitty tune, faulty brake switch, engine misfire, engine/trans overtemp, certain trouble codes etc etc
2. Why is lockup not engaging when commanded manually? Possible causes include warn TCC regulator valve, failed or leaking PWM solenoid, failed or leaking TCC Apply solenoid, paralyzed TCC Apply valve in pump. Pull the pan and remove both pwm and tcc apply solenoids. Command them on with scan tool and see if they 'click' and hold pressure. Check them for cracks. Use the pick to actuate the apply valve and see if it moves freely in its bore.
Getting trans pressure readings could be helpful also.
The brake switch is brand new and verified with multimeter to be working correctly. I have my misfire tables zero'd out.
The apply valve in the VB?
I will post the most recent tune and log here,
Thread Starter
Teching In
Joined: Jan 2009
Posts: 37
Likes: 2
From: Ionia, Michigan
So today I pulled the codes and got the following.
0x10: P0463 - Fuel Level Sensor A Circuit High (Pending, Current)
0x10: P0522 - Engine Oil Pressure Sensor/Switch Circuit Low (Current)
0x10: P0650 - Malfunction Indicator Light Control Circuit (Pending, History)
0x10: P0654 - Engine RPM Output Circuit (Pending, History)
0x10: P1571 (Pending, History)
0x10: P1689 (SES, Current)
0x10: P1860 (Pending)
I set everything except the last 2 to no MIL reported. Not sure if the P1860 indicates the TCC solenoid is actually bad, or if it could have been caused by one of the earlier codes. I'll take it for a drive tomorrow and see.
0x10: P0463 - Fuel Level Sensor A Circuit High (Pending, Current)
0x10: P0522 - Engine Oil Pressure Sensor/Switch Circuit Low (Current)
0x10: P0650 - Malfunction Indicator Light Control Circuit (Pending, History)
0x10: P0654 - Engine RPM Output Circuit (Pending, History)
0x10: P1571 (Pending, History)
0x10: P1689 (SES, Current)
0x10: P1860 (Pending)
I set everything except the last 2 to no MIL reported. Not sure if the P1860 indicates the TCC solenoid is actually bad, or if it could have been caused by one of the earlier codes. I'll take it for a drive tomorrow and see.
On The Tree
Joined: Sep 2018
Posts: 161
Likes: 4
From: New Zealand
the p1860 code is very much likely to be your issue. You need to check the PWM solenoid on the valve body to see if it works. Pull the solenoid and command it on with your scanner. see if it clicks and if you can blow through it when commanded on. If its not clicking you need to check the wiring going to it and the solenoid itself.
Thread Starter
Teching In
Joined: Jan 2009
Posts: 37
Likes: 2
From: Ionia, Michigan
the p1860 code is very much likely to be your issue. You need to check the PWM solenoid on the valve body to see if it works. Pull the solenoid and command it on with your scanner. see if it clicks and if you can blow through it when commanded on. If its not clicking you need to check the wiring going to it and the solenoid itself.
One question. I do not have an Input Speed Sensor on this. It's segment swapped. I've seen conflicting information, is the ISS needed on a segment swap or not?
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TECH Junkie
Joined: Jun 2008
Posts: 3,202
Likes: 1,390
From: Nitro Alley
So today I pulled the codes and got the following.
0x10: P0463 - Fuel Level Sensor A Circuit High (Pending, Current)
0x10: P0522 - Engine Oil Pressure Sensor/Switch Circuit Low (Current)
0x10: P0650 - Malfunction Indicator Light Control Circuit (Pending, History)
0x10: P0654 - Engine RPM Output Circuit (Pending, History)
0x10: P1571 (Pending, History)
0x10: P1689 (SES, Current)
0x10: P1860 (Pending)
I set everything except the last 2 to no MIL reported. Not sure if the P1860 indicates the TCC solenoid is actually bad, or if it could have been caused by one of the earlier codes. I'll take it for a drive tomorrow and see.
0x10: P0463 - Fuel Level Sensor A Circuit High (Pending, Current)
0x10: P0522 - Engine Oil Pressure Sensor/Switch Circuit Low (Current)
0x10: P0650 - Malfunction Indicator Light Control Circuit (Pending, History)
0x10: P0654 - Engine RPM Output Circuit (Pending, History)
0x10: P1571 (Pending, History)
0x10: P1689 (SES, Current)
0x10: P1860 (Pending)
I set everything except the last 2 to no MIL reported. Not sure if the P1860 indicates the TCC solenoid is actually bad, or if it could have been caused by one of the earlier codes. I'll take it for a drive tomorrow and see.
The DTC: P1689 would normally indicate that the engine control module can not communicate with the "Fuel Pump Flow Control Module".
Are you using a returnless fuel system with the OEM pump from the original vehicle?
The DTC: P0463 may also be related to this if you have some incorrect or intermittent wiring connections...
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Verdad Gallardo TECH Junkie
Joined: Jun 2008
Posts: 3,202
Likes: 1,390
From: Nitro Alley
Ahh... This explains things...
Lets think about that in a very simple manor.
1st. On Board Diagnostics is very very stupid. It does not have a brain, nor anything remotely close in terms of intelligence.
2nd. If there was...
I am sorry, never mind what I was going to say... It would have probably gone over peoples heads and been a waste of time.
Being that you have multiple DTCs of multiple types... Just get yourself an Input Speed Sensor installed, and start there.
Then take a look at the PWM TCC circuit (you may not have much going on there).
Without any measurement of the turbine speed... the engine/ transmission control module has no idea of how much pressure to push for TCC apply, the timing for TCC operation.
The ECM/ TCM has no idea if there is any slipping from the torque converter/ transmission... among many other tings.
Thread Starter
Teching In
Joined: Jan 2009
Posts: 37
Likes: 2
From: Ionia, Michigan
Ahh... This explains things...
Lets think about that in a very simple manor.
1st. On Board Diagnostics is very very stupid. It does not have a brain, nor anything remotely close in terms of intelligence.
2nd. If there was...
I am sorry, never mind what I was going to say... It would have probably gone over peoples heads and been a waste of time.
Being that you have multiple DTCs of multiple types... Just get yourself an Input Speed Sensor installed, and start there.
Then take a look at the PWM TCC circuit (you may not have much going on there).
Without any measurement of the turbine speed... the engine/ transmission control module has no idea of how much pressure to push for TCC apply, the timing for TCC operation.
The ECM/ TCM has no idea if there is any slipping from the torque converter/ transmission... among many other tings.
Lets think about that in a very simple manor.
1st. On Board Diagnostics is very very stupid. It does not have a brain, nor anything remotely close in terms of intelligence.
2nd. If there was...
I am sorry, never mind what I was going to say... It would have probably gone over peoples heads and been a waste of time.
Being that you have multiple DTCs of multiple types... Just get yourself an Input Speed Sensor installed, and start there.
Then take a look at the PWM TCC circuit (you may not have much going on there).
Without any measurement of the turbine speed... the engine/ transmission control module has no idea of how much pressure to push for TCC apply, the timing for TCC operation.
The ECM/ TCM has no idea if there is any slipping from the torque converter/ transmission... among many other tings.