Engine/Transmission (1998.5 - 2002) MAP sensor resistance?? Code ECU 237

[TractorNut]

Headed home after the Tractor Pull last night. . and NO POWER... The mighty Cummins could only muster 12psi of Boost... box on (3x5) A fun ride home pulling the tractor at only 50mph...

Checked the codes. . ECU 0237 (low Boost sensor voltage)

Unplugged the box. . and it runs better. . and I can get over 20psi of boost. . (but still feels weak. )

But. . I unhooked the batteries for about 15mins, and the code either didn't clear. . or is still remaining... (Will this code clear like this or do I need to get a scan tool??)

I have been running my DDUFM for about 1 yr and half with no problems. . (about 65,000 miles) Does anyone know the sensor resistance of the sensor in the Norm??? I want to rule this out before I call DD... (it will be Friday before I can get to a scan tool I should be able to check the sensor voltage from there)



I have tried unplugging the sensor connectors, grounds, and power source, and main plug for the DDUFM. . same results... but you can change the levels and it does make a difference in power(and boost pressure on 5x5 it got about 20 psi)

Just needing a little help guys...

Thanks. .

Bryan

 

[Little Bill]

Don't know the resistance values but I do have the voltage output values. Sensor input is 5v.



Boost Voltage

0 1. 045

6 1. 48

10 1. 75

15 2. 05

18 2. 27

20. 5 2. 44

 

[TractorNut]

One more question. . about the voltages... Is that taken off a scanner or actual?? (should be the same) yup should be 5 volts in... I've got some time today. . I'll check to make sure I'm getting the 5volts throught the box wiring harness. . and I should be able to rig up the connectors to measure the voltage with a meter while driving... Thanks for the numbers...

I'm afraid its point to a failure in the box after I drove it today it seems to be like a stock truck. . (. . all normal with the box unpluged. ) I am guessing the code will clear after X number of starts... )

Bryan



Edit. . Its sure doesn't use much of the range of the sensor... I guess for other application they allow for more boost pressure... .

 

[Little Bill]

I took the readings off the sensor, both in the truck and on the bench. The sensor reads 1 volt/atmosphere (absolute) and has a range of -30 inches Hg to 58. 8 psi.

 

[TractorNut]

Thanks again for the info... My Check engine light went off yesterday. . I have had the box unplugged for 2 days now. . and it finally cleared it self. . (the light anyways. . code is still there. . ) I plugged the box back in and got the light back on... I am going to take the voltage reading where the wires come into the comp box and leave the comp box. . that should point me at the exact location of the fault...

Thanks

Bryan



(14. 7 Absolute= 0 gage psi... should be close enough, to check from your numbers... I think I'm only at about 500ft. )