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VCC engagement problem (PCM code E039)


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I have encountered a wierd problem with my 92 STS and was wondering if anyone else has seen this.

After tanking up at BP/Amoco somewhere in Michigan (exit 168 on highway 69) and driving for a while the dreaded "service engine soon" light popped up. The error code was E039 which translate to VCC engagment problem.

Not assocciating that it might be related to the BP gas I put in another tank of BP gas in Joliet, IL. The problem continued to occur after each ignition cycle.

After pulling into another BP gas station in De Soto in IL, I noticed all the premium gas pumps were out of order and the the attendant told me that he didn't know what the problem was and could have been contaminated with water or bad gas.

After putting in two more tanks of premium gas of other brands (Phillips 66 and Shell) and using cruise control for most of the way, the service engine soon light did not occur. Then I went off cruise and still the service engine light did not come on.

Has anyone encountered similar problem? Could a bad tank of gas cause such a problem. (The problem by the way is high rev with no or slow increase in vehicle speed in top gear). Could the Trottle position sensor (TPS) be thrown out of wack because of the bad gas and causing the PCM to misinterpret and shutting off the VCC?

By the way, earlier in this forum I mentioned that I put in Mobil synthetic ATF. What's your experience with this stuf?

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Thanks Bbobynski.

Too good to be true :( . You are right... it occurred again while I was on a grade near the highest point on I-80 at the Lincoln monument in WY.

I will try your test later and let you know if the VCC release when tapping the brake in the 4th gear.

If indeed the E039 is caused by slippage, would you recommend using Lucas tranny fix additive before I visit the dealer?

Thanks again.

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Bbobynski, pardon my ignorance, how does one know when the VCC is on? I tried the check you suggested at a speed of about 100 km/h (62 mph), tach at 2000 rpm and coolant temp at about 94 C (201 F). rpm did not change when I tapped the brake. Did not get the "service engine light though".

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  • 3 weeks later...
There is a lot in the archives on the VCC if you search for "VCC" "TCC" "Torque converter clutch" "viscous converter clutch" etc....

I went through the archives and they were very informative.

I then went through these tests and the results are:

- Resistance at solonoid A, B TCC/VCC and PWM/MOD all tested within specification.

- power was present at the vehicle harness ~12 volts

- brake switch tested ok through onboard diagnostics-PCM inputs E171 (VCC brake) as well as test at engine harness.

-solonoid A, B and tested ok when appropriate wire was grounded on the engine harness (click heard and current ~.5 A). However, TCC/VCC and PWM solonoid did not have a current flow when grounded to the engine harness although the correct current flow was observed when grounded to engine block and the solonoid click could be heard.

I then checked the continuity between the VCC apply jack and PCM harness pin 3F6 and between VCC MOD jack and PCM harness pin 3F5 and both showed continuity.

The diagnostic chart ends with PCM replacement check.

I also performed the TCC/VCC test by shifting to D3 with engine on and connecting engine harness pin E (power source) to tranny connector pin A and then connecting a jumper wire to tranny connector D (VCC apply). The engine did not stall indicating the VCC did not apply. It also did not stall when grounded to engine block.

My question is: should I replace the PCM? or are the test results indicating something else. I am thinking it's a bad PCM, but am concern that the engine did not stall when I grounded tranny connector pin D (VCC apply) to the engine block. Would a bad PCM fail this test.

Any help would be much appreciated.

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Thanks once again Bbobynski.

Just wondering if it's possible to diagnose whether the PCM is grounding the TCC/VCC by jumpering the TCC/VCC connection at the engine harness and tranny connector with an ammeter in between and going into diagnostic mode (engine off) - into outputs - E002 VCC sol - and looking to see if the VCC solenoid is energized.

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Did some more test by going into diagnostic - PCM overide - ES01 VCC sol - and while driving at about 60 mph, rpm @ ~2000 tried to energize the VCC solenoid by pressing the warmer button. The ECCP did display 99. Then tried to de-energize the VCC by pressing the cooler button and the ECCP displayed 00. Whille I was doing this I did not notice any change in rpm suggesting the VCC did not engage.

What can I conclude from the above test? The PCM seems to be commanding (ECCP displays 99), but is that any indication that it is actually grounding the VCC apply circuit?

your input is much appreciated.

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You can also run that VCC apply jumper wire inside the car and drive the car. At normal highway speeds you can "manually" apply the VCC by simply grounding that wire inside the passenger compartment. Run that VCC jumper wire to a toggle switch or push button switch and then to ground. The VCC should apply when that wire is grounded as you surmised. If it still cannot be forced to apply with the manual grounding of the wire with the car running down the road then I wouldn't suspect the PCM at all.

Thanks for clarifying!

The wiring setup I had while testing was pretty flimsy and so I am guessing that when you suggest running jumper wire to inside the car, I should use another engine harness connector to get a good connection to the tranny connector as well as to the engine harness connector? I am going to try the local salvage yard to see if I can find an extra connector.

What point inside the car would be a good ground connection?

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Or, like you mentioned, you could put an amp meter on the line to see if current is flowing when the PCM tries to apply the VCC. If so, then you could assume the PCM was working correctly.


Did the above test and got the 0.5 amps flow through the VCC solenoid when I cycled the VCC through the output in diagnostic mode. Looks like the PCM is commading the VCC ok. Tried the stall test in D3 again but could not get it to stall when grouding the VCC solenoid.

I forgot to mention that few months earlier, I had the tranny cooler line bust on me while going up a hill and in the process lost most of the tranny fluid. Is it possible that could have killed the converter clutch?

Don't know what I should do next. Should I just drive it the way it is as it drive ok except no VCC engagement? :unsure:

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