Power logger not getting transmission data?

[m3x1c0]

Simply put: I have a log showing me going 89 mph at 19psi in Park/Neutral. When I put car in reverse it doesn't show the checkmark by the P/N but then in drive goes back to Park. Switch works fine, reverse lights work and the Scanmaster knows I'm in park (good for changing chip settings with car off INT 12 for example.) Not sure what could cause this. PLC on my laptop is up to date. Not sure on firmware in the PL haven't figured out how to check that but these features worked fine up until recently. Also do not see any TCC lockup. I'm a total noob and don't know if I could tell it was in lockup unless the PL shows it. Steve said he didn't feel it lockup though.

Any ideas how to fix this?

 

[TurboDave]

About the only explanation is that the linkage from the tranny up to the column is misadjusted.

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[m3x1c0]

About the only explanation is that the linkage from the tranny up to the column is misadjusted.

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Could you point me to a thread showing proper adjustment?

 

[m3x1c0]

Resurrecting this old thread because I still haven't figure out this problem. Also I believe that whatever is causing this is also keeping the converter from locking up while cruising. I plan on tracing the wires but not sure which one controls the tranny. Any advice before I go digging around tonight?

 

[TurboBob]

converter logic does not check P/N switch. Just the 3rd and 4th inputs, TPS, and MPH

Bob

 

[m3x1c0]

converter logic does not check P/N switch. Just the 3rd and 4th inputs, TPS, and MPH

Bob

Ok so the P/N switch issue is unrelated. I'm getting TPS and MPH so I need to check the 3/4 inputs as I do not see those on my PL files. My rpm cruising seems too high so Im guessing the lockup function is not working correctly. Not being well versed with this stuff: is the lockup controlled by the chip? Could the lockup have been disabled by the chip programming?

 

[m3x1c0]

Some additional info: My car will not start in neutral. I believe my column might be out of adjustment. I will check that.

Edit: I dont believe this has anything to do with converter problem per Bob's comment above.

 

[TurboBob]

the starting lockout in the column is mechanical if I remember correctly, there is nothing electrical in the column that would prevent starting.

the ECM/chip controls the lockup. It could be programmed to never lock, but most chip guys don't bother since there is no issue with the non-lock converters.

there is a brake pedal switch in the circuit, but the ECM is not aware of it. So the ECM will lock the converter when it sees the appropriate conditions of TPS, MPH, and gear.

Bob

 

[m3x1c0]

the starting lockout in the column is mechanical if I remember correctly, there is nothing electrical in the column that would prevent starting.

the ECM/chip controls the lockup. It could be programmed to never lock, but most chip guys don't bother since there is no issue with the non-lock converters.

there is a brake pedal switch in the circuit, but the ECM is not aware of it. So the ECM will lock the converter when it sees the appropriate conditions of TPS, MPH, and gear.

Bob

Gotcha. The issues must lie on the 3 and 4 inputs then. According to my logs the ECM never commands lockup and I also never see the 3 or 4 gear inputs light up. I intend to check the wiring of the highlighted circuits below. Is there a way to test the 3 and 4 inputs with the car stationary?

 

[TurboBob]

measure the voltage at those pins, then unplug the electrical connector at the trans and measure again

Bob

 

[m3x1c0]

measure the voltage at those pins, then unplug the electrical connector at the trans and measure again

Bob

Thank you for the info! Is it ok to leave the ECM connector unplugged while measuring with key-on or will I need to backprobe with a pin?

 

[TurboBob]

well, the voltage source that circuit is the ECM, so unplugging it would invalidate the test.

try this. unplug the connector at the transmission, and then see what the PowerLogger shows.

B

 

[m3x1c0]

well, the voltage source that circuit is the ECM, so unplugging it would invalidate the test.

try this. unplug the connector at the transmission, and then see what the PowerLogger shows.

B

Ok will do. If I can sneak a backprobe in without damaging anything I'll give a shot as well. Thanks again Bob.

 

[TurboDave]

the starting lockout in the column is mechanical if I remember correctly, there is nothing electrical in the column that would prevent starting.

the ECM/chip controls the lockup. It could be programmed to never lock, but most chip guys don't bother since there is no issue with the non-lock converters.

there is a brake pedal switch in the circuit, but the ECM is not aware of it. So the ECM will lock the converter when it sees the appropriate conditions of TPS, MPH, and gear.

Bob

But if the brake switch is misadjusted, it will not allow lockup.


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[m3x1c0]

But if the brake switch is misadjusted, it will not allow lockup.


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In this case the issue is that the ECM is not even commanding the converter to lockup. As Bob mentioned before, the ECM is unaware of that switch so it would still show the lockup on the powerlogger even if the converter was not physically locked up. At least this is how I understand it.

 

[m3x1c0]

well, the voltage source that circuit is the ECM, so unplugging it would invalidate the test.

try this. unplug the connector at the transmission, and then see what the PowerLogger shows.

B

Finally got a second to try this. I'll upload the log later but Unplugged the 3 and 4 gear lights up on log. Plug it back in and in park it does not show the Park/neutral light. In neutral it does show the Park/Neutral light. No visible damage to the wires or corrosion on the pins but I plan on taking a closer look at the wiring this weekend. I'm beginning to suspect an issue with the Internal solenoid. What's your take Bob?

 

[TurboBob]

park/neutral is not in the transmission, its on the steering column under the dash, controlled by the collar that rotates.

3 & 4 are switches inside the trans. could be that the trans builder removed the switches, and grounded the wires (some trans builders don't like the switches)

B

 

[m3x1c0]

park/neutral is not in the transmission, its on the steering column under the dash, controlled by the collar that rotates.

3 & 4 are switches inside the trans. could be that the trans builder removed the switches, and grounded the wires (some trans builders don't like the switches)

B

Good timing then, I plan to drop the pan and do a filter and fluid change soon. I will check in there. I am fairly certain that the 3 and 4 switches worked before the engine was rebuilt however. I will have to go dig up some of older logs.

 

[Steve V]

Jump pins A to F on aldl......if you here a click thats the solnoid in the pan clicking. It will be heard in the very front of the pan behind convertor. If it does not click unplug the trans connector and ohm the solnoid there 20 ish ohms as long as its not shorted its fine. The ecm does not see 3 and 4 inputs it will not try to lock the convertor. Its possible the switches on the valvebody have bad diaphram. Cheap and easy to replace. Can remove switchs hook up to a meter and use air to test as well. And just for grins you can bypass the brake switch if you want for testing. But without 3/4 input it won't try to lock. There should be power at the trans with KOEO unless the switch is depressed. The ecm grounds the solnoid IIRC. You know where I am if you want to rack it up pull the pan and have a look.

 

[m3x1c0]

Jump pins A to F on aldl......if you here a click thats the solnoid in the pan clicking. It will be heard in the very front of the pan behind convertor. If it does not click unplug the trans connector and ohm the solnoid there 20 ish ohms as long as its not shorted its fine. The ecm does not see 3 and 4 inputs it will not try to lock the convertor. Its possible the switches on the valvebody have bad diaphram. Cheap and easy to replace. Can remove switchs hook up to a meter and use air to test as well. And just for grins you can bypass the brake switch if you want for testing. But without 3/4 input it won't try to lock. There should be power at the trans with KOEO unless the switch is depressed. The ecm grounds the solnoid IIRC. You know where I am if you want to rack it up pull the pan and have a look.

Ok I can definitely do the ALDL test before I drive over. I was planning on dropping the pan doing a filter/fluid change but couldn't find jackstands high enough LOl. Definitely will be in contact with you soon.