Need up to speed on our electronics

[015point9]

I could use some schooling of what you think would be the best way for someone that knows very little about our electronics work on our trucks.  I've have read somewhat...between the net and dodge manuals so I do have a general understanding.  I do use a code reader to track down problems.  But many postings goes over my head quickly.  

Anybody care to share how you learned about how these electronic machines on wheels work?  

 

(Telling my age)  I'm willing to trade...if you need to set your points or cam angle or find which coil over plug is bad...i can help.???

 

Any help appreciated to material that would get me up to speed for our 2nd gens.  Alot of stuff i've looked at online is very general.  

[Marcus2000monster]

7 minutes ago, 015point9 said:

I could use some schooling of what you think would be the best way for someone that knows very little about our electronics work on our trucks.  I've have read somewhat...between the net and dodge manuals so I do have a general understanding.  I do use a code reader to track down problems.  But many postings goes over my head quickly.  

Anybody care to share how you learned about how these electronic machines on wheels work?  

 

(Telling my age)  I'm willing to trade...if you need to set your points or cam angle or find which coil over plug is bad...i can help.???

 

Any help appreciated to material that would get me up to speed for our 2nd gens.  Alot of stuff i've looked at online is very general.  

I too would like to get schooled. 

[Mopar1973Man]

@Chris O. is the site guru of the CCD network. Might ask him about some of the stuff. 

[Me78569]

You need to be more specific as to what you want to start with.  What do you want to know? 

 

the biggest thing to help you get through electrical stuff is to take it one step at a time and don't let it get over your head.   

[Marcus2000monster]

24 minutes ago, Me78569 said:

You need to be more specific as to what you want to start with.  What do you want to know? 

 

the biggest thing to help you get through electrical stuff is to take it one step at a time and don't let it get over your head.   

Tell me all about ECMs and PCMs...

[015point9]

39 minutes ago, Me78569 said:

You need to be more specific as to what you want to start with.  What do you want to know? 

 

the biggest thing to help you get through electrical stuff is to take it one step at a time and don't let it get over your head.   

 

Ok for example and just opening up my book...page 85 is code p-0236, map sensor too high too long has 9 steps and the "verifiacation" test has 39 steps.  On many postings, some people on here can solve the problem in about 3 sentences.  How long did it take and how did you learn... to cut thru all the "chatter" to hone in and know what the problem is.

 

 

Edited February 22, 2018 by 015point9
Add pic

[dripley]

52 minutes ago, 015point9 said:

I could use some schooling of what you think would be the best way for someone that knows very little about our electronics work on our trucks.  I've have read somewhat...between the net and dodge manuals so I do have a general understanding.  I do use a code reader to track down problems.  But many postings goes over my head quickly.  

Anybody care to share how you learned about how these electronic machines on wheels work?  

 

(Telling my age)  I'm willing to trade...if you need to set your points or cam angle or find which coil over plug is bad...i can help.???

 

Any help appreciated to material that would get me up to speed for our 2nd gens.  Alot of stuff i've looked at online is very general.  

I will tell you my age, grab a match book striker to clean up your points and turn the distributed cap to get your timing close. Coil overs had me scratchin head when I first saw them. The only tools you needed then was a hammer, case knife, and never show up with out a coat hanger and some duct tape. 

[Me78569]

28 minutes ago, Marcus2000monster said:

Tell me all about ECMs and PCMs...

More specific, that's a big bite.

 

Quote

Ok for example and just opening up my book...page 85 is code p-0236, map sensor too high too long has 9 steps and the "verifiacation" test has 39 steps.  On many postings, some people on here can solve the problem in about 3 sentences.  How long did it take and how did you learn... to cut thru all the "chatter" to hone in and know what the problem is.

Well if you have a root understanding of how the 5v reference sensors work it becomes a lot easie.  

 

So 5v sensors.  typically 3 leads

1 lead is a 5v source to power the sensor.  If you don't have 5v to the sensor then you have a wiring issue between the ecm and sensor

1 lead is ground.  if you dont have ground ( you are completing the cirucit by measuring between orange wire and black) 

1 leads is the output from the sensor

 

as pressure moves from 0 psi to 50 psi you should see the output from the sensor decrease in voltage. 0 psi = 4.5v, 52 psi = .5v    

 

We call that a pull down sensor,  as the sensor value increases the output from the sensor increases

 

So the code is saying sensor too high too long.   

Quote

Testing

1. Turn ignition on with engine off. Using DRBIII(R) scan tool, check for engine DTCs. If any other MAP sensor related DTC exist, perform appropriate test. See DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no other MAP sensor related DTCs exist, go to next step.

2. Turn ignition off. Perform turbocharger boost pressure test. See TURBOCHARGER under AIR INDUCTION SYSTEMS in SYSTEM & COMPONENT TESTING - RAM PICKUP - DIESEL article. If boost pressure is not within specification, repair as necessary. If boost pressure is within specification, go to next step.

3. Ensure ignition is off. Disconnect MAP sensor harness connector. MAP sensor is located on driver's side rear corner of cylinder head. Turn ignition on with engine off. Using DVOM, measure voltage between ground and terminal No. 1 (Orange wire) on MAP sensor harness connector. If voltage is 4.7-5.3 volts, go to next step. If voltage is not 4.7-5.3 volts, repair Orange wire between MAP sensor and ECM. ECM is located on driver's side of engine, just in front of fuel transfer pump and contains a 50-pin connector.

4. Ensure MAP sensor harness connector is still disconnected and ignition is on with engine off. Using DVOM, measure voltage between terminals No. 1 (Orange wire) and No. 3 (Black/Light Blue wire) on MAP sensor harness connector. If voltage is 4.7-5.3 volts, go to next step. If voltage is not 4.7-5.3 volts, repair open in Black/Light Blue wire between MAP sensor, oil pressure sending unit and ECM.

5. Ensure MAP sensor harness connector is still disconnected and ignition is on with engine off. Using scan tool, read MAP sensor voltage. If MAPsensor voltage is .42-.58 volt, go to next step. If MAP sensor voltage is not .42-.58 volt, replace MAP sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article.

6. Turn ignition off. Ensure MAP sensor harness connector is still disconnected. Disconnect ECM harness connector. ECM is located on driver's side of engine, just in front of fuel transfer pump and contains a 50-pin connector. Using DVOM, measure resistance of Gray/Red wire between terminal No. 2 on MAP sensor harness connector and terminal No. 8 on ECM harness connector. If resistance is less than 10 ohms, go to next step. If resistance is 10 ohms or greater, repair open in Gray/Red wire between MAP sensor and ECM.

7. Using DVOM, measure resistance between terminal No. 1 (Orange wire) and terminal No. 2 (Gray/Red wire) on MAP sensor harness connector. If resistance is 1000 ohms or greater, go to next step. If resistance is less than 1000 ohms, repair short between MAP sensor signal circuit (Gray/Red wire) and MAP sensor 5-volt supply circuit (Orange wire).

8. Using DVOM, measure resistance between terminal No. 3 (Black/Light Blue wire) and No. 2 (Gray/Red wire) on MAP sensor harness connector. If resistance is 1000 ohms or greater, go to next step. If resistance is less than 1000 ohms, repair short between MAP sensor ground circuit (Black/Light Blue wire) and MAP sensor signal circuit (Gray/Red wire).

9. Using DVOM, measure resistance between ground and terminal No. 2 (Gray/Red wire) on MAP sensor harness connector. If resistance is 1000 ohms or greater, replace and program the ECM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. If resistance is less than 1000 ohms, repair short to ground in Gray/Red wire between ECM and MAP sensor.

 

 

So too high too long means the ecm see's that the engine is "off" ka no load,  logic tells us that map readings should be at 0 psi.  If it is above that we know that something is wrong, it is impossible to have positive boost without the engine running.

 

the too high too long means the ecm is seeing high voltage on the sensor when it shouldn't be.  If you look at step 3 above you can see the troubleshooting tree wants sub .5v on the output from the wiring AKA no outside power feeding into the system.   

 

so if you can isolate a condition, engine off, you can predict that a sensor should act in a specific manner.  If it doesn't then you can point to a issue.  

 

 

clear as mud?

 

Edited February 22, 2018 by Me78569

[dripley]

Ahh yeah!!!!!

[IBMobile]

It took me 48 years of working on them and watching YouTube for an hour to figure this stuff out.  

[Dieselfuture]

My grandfather always said before trying to solve a problem you first need to understand it. 

[015point9]

Op here...thanks for replies.

 

How easy is it to screw up those elec components in my learning?  Obviously not going to on purpose, and fused protected if I do?

[Me78569]

pretty dang hard haha  I wouldn't worry.    You will have a "this isn't a good idea" thought long before you do something bad enough to burn much of anything up.

[Mopar1973Man]

Most of the problems on our truck tend to be the basic stuff. Fuses, bad connections, broken wire, bad grounds. Going beyond that you getting into digital technology and logic thinking. Lot of people just can't think in logic so the maybe or it could be pops out. That's human to say that. Logic is its on or off but there is no maybe.