Author Topic: Need help to troubleshoot MAP input  (Read 5635 times)

Offline SPatrickB

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Need help to troubleshoot MAP input
« on: December 30, 2013, 01:13:35 am »
I have an issue with the MAP input where the kpa value (in VemsTune) appears to stay around 75 - 80 kpa irrespective of how I drive the (supercharged) car.
I use an external 2 bar sensor and the VEMS 3.6 was ordered and came without the onboard sensor.
When I have the ignition on, I see good ground, 5v at the sensor supply with about 2.5v output to the correct pin (6) on VEMS. When I apply mouth suction I see a drop of ~1 volt, so it appears the sensor is working OK.
Another symptom is when the VEMS is initially powered, the kpa starts very low and creeps up to 80 after a minute or so which to me gives the appearance that the signal is floating perhaps.

Any ideas?
« Last Edit: December 30, 2013, 02:52:02 am by SPatrickB »

Offline GintsK

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Re: Need help to troubleshoot MAP input
« Reply #1 on: December 30, 2013, 08:52:01 am »
That another symptom clearly shows that sensor output do not reach the board.

Gints

Offline SPatrickB

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Re: Need help to troubleshoot MAP input
« Reply #2 on: December 30, 2013, 09:14:59 am »
OK, I'll pull out the board and trace continuity.....

Offline SPatrickB

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Re: Need help to troubleshoot MAP input
« Reply #3 on: December 30, 2013, 01:05:31 pm »
Ah...EC18 pin 6 pad to pin 1 MPX4250AP hole. Missed that one.
Wow, I drove a lot of Kms on one MAP value!  :o

Offline Kamuto

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Re: Need help to troubleshoot MAP input
« Reply #4 on: December 30, 2013, 10:05:49 pm »
Ah...EC18 pin 6 pad to pin 1 MPX4250AP hole. Missed that one.
Wow, I drove a lot of Kms on one MAP value!  :o
lucky you  :D
Vems installer in Lithuania
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