Lime Green Connector - Where does is connect to?

MikeRiderTB

Original poster
Member
Nov 15, 2014
2
While reinstalling the exhaust pipe on my TB I noticed a Lime green connector with 2 contacts, hanging from the power steering fluid canister that is also part of the harness that runs in front of the engine cover. Anyone know where this goes? I had never noticed it before and don't think I disconnected it while removing the exhaust pipe. I will greatly appreciate an answer to this.
 

MikeRiderTB

Original poster
Member
Nov 15, 2014
2
Thank you very much Chris. that's it. Was wondering why I did not get a code indcating it was not connected. Well thanks again, Mike
 

The_Roadie

Lifetime VIP Donor
Member
Nov 19, 2011
9,957
Portland, OR
The connector just goes to a switch on the I6 engine. The zero oil pressure on the gauge could have been your only clue. The V8 has a real sensor whose absence could be detected by the computer.
 

IllogicTC

Member
Dec 30, 2013
3,452
The_Roadie said:
The connector just goes to a switch on the I6 engine. The zero oil pressure on the gauge could have been your only clue. The V8 has a real sensor whose absence could be detected by the computer.
Isn't the oil switch a normally-closed switch, relying on a certain pressure to open the circuit? In this case, it would report all is well. Seat belt switch in the buckle, and the stop lamp switch in some vehicles (can't recall if that includes ours off-hand, but have seen others), act the same way too.
 
  • Like
Reactions: MikeRamTB

AtlWrk

Member
Dec 6, 2011
674
I can confirm that a disconnected oil pressure switch on the I6 does NOT give any indication that something is wrong :hissyfit:

Didn't believe it until I tried it myself. Disconnected the switch and started it up: no lights, no warning, oil pressure gauge at its usual BS 40psi reading...

Seems trivial for the PCM to check for continuity through the switch before cranking to confirm it's connected. :blinkhuh:
 

IllogicTC

Member
Dec 30, 2013
3,452
AtlWrk said:
I can confirm that a disconnected oil pressure switch on the I6 does NOT give any indication that something is wrong :hissyfit:

Didn't believe it until I tried it myself. Disconnected the switch and started it up: no lights, no warning, oil pressure gauge at its usual BS 40psi reading...

Seems trivial for the PCM to check for continuity through the switch before cranking to confirm it's connected. :blinkhuh:
That's actually a very sound idea, that they should have implemented. Though then again, couldn't we check it ourselves? Turn the key to on but don't crank, with the pressure switch disconnected, and see if the gauge goes up anyway.
 

AtlWrk

Member
Dec 6, 2011
674
No such luck. The pressure gauge stays at zero until the engine is actually running. The software engineers realllly went out of there way to hide the fact that the gauge is a total lie <sigh>

When every other component gets an insane amount of continuous diagnosis...the PCM can't/won't tell you if arguably the most important sensor is functional? :eyebrowhuh:

I have hypothesized in similar rants that the PCM can actually know if there is sufficient oil pressure based on feedback from the exhaust cam timing. If it has control of the cam phaser, there must be oil pressure. So who really cares whether or not the switch is working? But if that's the case, why have the switch at all?
 

IllogicTC

Member
Dec 30, 2013
3,452
AtlWrk said:
No such luck. The pressure gauge stays at zero until the engine is actually running. The software engineers realllly went out of there way to hide the fact that the gauge is a total lie <sigh>

When every other component gets an insane amount of continuous diagnosis...the PCM can't/won't tell you if arguably the most important sensor is functional? :eyebrowhuh:

I have hypothesized in similar rants that the PCM can actually know if there is sufficient oil pressure based on feedback from the exhaust cam timing. If it has control of the cam phaser, there must be oil pressure. So who really cares whether or not the switch is working? But if that's the case, why have the switch at all?
If the solenoid was operating at 0% duty cycle, there would be little/no flow to the phaser, and in this particular situation an oil switch would be useful. There are also a number of other factors that may lead to VVT failure that may not be lack of oil, while the switch itself is all about having a specified minimum pressure.

Thinking on it, P0014 -- Exhaust timing over-advanced. As the duty cycle increases, the phase angle retards. 0% duty cycle is 0-degrees, and it can be increased in 10% increments, to a 100% duty cycle at 25-degree retard. Over-advance could show a lack of oil pressure, but we all know that solenoid makes that pop up a lot, too. People wouldn't suspect it.
 

Forum Statistics

Threads
23,273
Posts
637,495
Members
18,472
Latest member
MissCrutcher

Members Online