Help - My CRD died on highway traveling 45 to 50 mph

WWDiesel · **Posted:** Sun Jun 21, 2020 9:37 pm

The only way to truly diagnose individual sensor issues one at a time is to have a very high end scanner like a SnapOn Verus Pro or a Bosch Diagnostic Scan Tool that allows you to view and monitor "live data" for each individual sensor while the engine is running or have a scope and back probe the connector to monitor the output signal coming for each one of the sensors to the ECM one at at time. None of these options are cheap or simple, high end test equipment costs thousands of dollars and then you must be well versed and trained in how to analyze and interpret the data your are viewing.
Nothing about these vehicles electronics is cheap or easy unfortunately.... :banghead:

DTC's may at least help guide you to the offending sensor or area of malfunction....

racertracer · **Posted:** Mon Jun 22, 2020 10:10 pm

WWDiesel wrote:

The only way to truly diagnose individual sensor issues one at a time is to have a very high end scanner like a SnapOn Verus Pro or a Bosch Diagnostic Scan Tool that allows you to view and monitor "live data" for each individual sensor while the engine is running or have a scope and back probe the connector to monitor the output signal coming for each one of the sensors to the ECM one at at time. None of these options are cheap or simple, high end test equipment costs thousands of dollars and then you must be well versed and trained in how to analyze and interpret the data your are viewing.
Nothing about these vehicles electronics is cheap or easy unfortunately.... :banghead:

DTC's may at least help guide you to the offending sensor or area of malfunction....

WWDiesel, that's a tough one to read.

racertracer · **Posted:** Mon Jun 22, 2020 10:11 pm

flash7210 wrote:

Here is my experience with the fuel rail pressure sensor and fuel quantity solenoid:

The components themselves didn’t fail.
It was the wiring harness connectors.
No visible damage. The fault was within the connector and was intermittent.
Engine would start and run but wiggling the connectors would cause the engine to sputter and stall.
Splicing in new connectors fixed the problem.

And with the fuel rail pressure solenoid:

The harness connector was good.
The fault was within the solenoid.
When cold, resistance through the solenoid was normal.
Once warmed up, the resistance would go high or open circuit. Engine dies and will not restart.

After replacing the rail pressure solenoid the engine would crank and crank and not start.
Bled the air from the rail and cleared the codes.
Took multiple attempts at bleeding and clearing codes until it finally started up and ran perfectly.

I replaced the connectors with used ones I had on the shelf... still no joy.

rankom · **Posted:** Mon Jun 22, 2020 11:33 pm

did you check compression? to see if valve train is healthy?

racertracer · **Posted:** Tue Jun 23, 2020 4:08 am

i really have no doubt about a healthy valve train. The engine was running fine, nolack of power, it just quit, electrical issues were present.

racertracer · **Posted:** Tue Jun 23, 2020 4:14 am

Cascade/Overflow Valve NA F00N200798.

I plan to remove and replace the Cascade/Overflow Valve NA F00N200798, any advice on what to look for?

WWDiesel · **Posted:** Tue Jun 23, 2020 3:18 pm

racertracer wrote:

Cascade/Overflow Valve NA F00N200798.
I plan to remove and replace the Cascade/Overflow Valve NA F00N200798, any advice on what to look for?

A few thoughts,
Did you ever find the original electrical short that triggered all the DTC's listed in your first post at the beginning of this thread?
Have you checked the wiring and connectors good going to the crankshaft and camshaft sensors? If either one shorted out, the engine would shut off and / or not restart.

Have you cleared the DTC's and rechecked to see if the DTC's come back? I read back through all the posts and could not find where you have cleared the DTC's.
If after clearing they come right back, you still have a short to ground somewhere and you must locate it first before replacing sensors.

Why are you replacing the Cascade/Overflow Valve, what led you to believe it is bad? Have you read the fuel rail pressure while trying to start the engine?
It takes ~4k pressure or better to start the engine.

If you still have a short to ground somewhere, it can pull down the 5 volt reference signal for the sensors from the ECM and prevent the engine from starting or running.

racertracer · **Posted:** Tue Jun 23, 2020 4:27 pm

WWDiesel wrote:

A few thoughts,
Did you ever find the original electrical short that triggered all the DTC's listed in your first post at the beginning of this thread?
Have you checked the wiring and connectors good going to the crankshaft and camshaft sensors? If either one shorted out, the engine would shut off and / or not restart.

Have you cleared the DTC's and rechecked to see if the DTC's come back? I read back through all the posts and could not find where you have cleared the DTC's.
If after clearing they come right back, you still have a short to ground somewhere and you must locate it first before replacing sensors.

Why are you replacing the Cascade/Overflow Valve, what led you to believe it is bad? Have you read the fuel rail pressure while trying to start the engine?
It takes ~4k pressure or better to start the engine.

If you still have a short to ground somewhere, it can pull down the 5 volt reference signal for the sensors from the ECM and prevent the engine from starting or running.

Did you ever find the original electrical short that triggered all the DTC's listed in your first post at the beginning of this thread? NO, I have not.

Have you checked the wiring and connectors good going to the crankshaft and camshaft sensors? If either one shorted out, the engine would shut off and / or not restart. I have not gone down below to check the wiring at the Crankshaft position sensor ... but i did replace the sensor with a brand new one.

Have you cleared the DTC's and rechecked to see if the DTC's come back? YES, I have. and they all came back.

Why are you replacing the Cascade/Overflow Valve, what led you to believe it is bad? It makes me feel good and keeps me from pulling my hair out.

If you still have a short to ground somewhere, it can pull down the 5 volt reference signal for the sensors from the ECM and prevent the engine from starting or running. OK, WWDiesel, going to do more digging into the harness. You brought me back from lala land. thanks

WWDiesel · **Posted:** Tue Jun 23, 2020 5:28 pm

What I would do.
Using your digital volt meter.
Starting at each sensor one at a time.
Most sensors will have either two or three wires going to them. One is 5 volt power supply, one is ground (3 wire), and second/third is sensor signal feed to/from ECM.
With ign. switch in the run position, (all fuses good)
Unplug each sensor one at a time and using voltmeter, check for the 5v power supply at each connector.
One of the wires should read 5v or slightly under.
If you find a sensor that does not have the 5v power supply, you have possibly have found your shorted wire, trace it back.
You can check the FSM wiring diagrams to view what each sensor should have under the "Connector Pinouts".
Report back, good luck,

Example:

flash7210 · **Posted:** Wed Jun 24, 2020 8:38 am

Yes, the rail pressure sensor is 5v

The rail pressure solenoid and fuel quantity solenoid are both 12v

My initial voltage checks all seemed good until I started wiggling wires, then open circuit

racertracer · **Posted:** Wed Jun 24, 2020 12:05 pm

flash7210 wrote:

Yes, the rail pressure sensor is 5v
The rail pressure solenoid and fuel quantity solenoid are both 12v
My initial voltage checks all seemed good until I started wiggling wires, then open circuit

He stated he is dealing with a short to ground according to DTC's, not an open circuit.

Flash, where is the rail pressure sensor and the rail pressure solenoid located?
1. Rail pressure sensor is 5v - Where is this sensor located?
on side of fuel rail
2. Rail pressure solenoid is 12v - Where is this solenoid located?
at end of fuel rail
3. Fuel quantity solenoid is 12v

flash7210 · **Posted:** Wed Jun 24, 2020 1:14 pm

racertracer wrote:

Flash, where is the rail pressure sensor and the rail pressure solenoid located?

1. Rail pressure sensor is 5v - Where is this sensor located?

2. Rail pressure solenoid is 12v - Where is this solenoid located?

3. Fuel quantity solenoid is 12v

1. in the middle of the fuel rail, has three wires

2. at the back of the fuel rail, next to the firewall, has two wires

3. on top of the CP3, has two wires

Note:
You can unplug the fuel quantity solenoid and the engine will start up and run.
In this way, all fuel is directed up to the rail and all fuel pressure modulation is controlled by the rail pressure solenoid.
If you unplug the rail pressure solenoid, the engine will not run at all. No pressure will build in the rail. All fuel will dump out through the return line from the rail.

racertracer · **Posted:** Wed Jun 24, 2020 1:36 pm

racertracer wrote:

flash7210 wrote:

Yes, the rail pressure sensor is 5v
The rail pressure solenoid and fuel quantity solenoid are both 12v
My initial voltage checks all seemed good until I started wiggling wires, then open circuit

He stated he is dealing with a short to ground according to DTC's, not an open circuit.

Flash, where is the rail pressure sensor and the rail pressure solenoid located?
1. Rail pressure sensor is 5v - Where is this sensor located?
on side of fuel rail
2. Rail pressure solenoid is 12v - Where is this solenoid located?
at end of fuel rail
3. Fuel quantity solenoid is 12v

Thank you

flash7210 · **Posted:** Wed Jun 24, 2020 1:53 pm

He stated he is dealing with a short to ground according to DTC's, not an open circuit.

The ECM cant tell the difference between a open circuit and a short to ground.
They both produce 0v at the end of the circuit.

But checking for a short to ground is pretty easy.
Disconnect the battery.
Use your volt-ohm meter to probe each wire, checking for continuity to chassis ground.

If you follow the diagnostic instructions in the shop manual, you will also be directed to check continuity from the ECM harness connector to the sensor/solenoid connector.

WWDiesel · **Posted:** Wed Jun 24, 2020 3:05 pm

flash7210 wrote:

He stated he is dealing with a short to ground according to DTC's, not an open circuit.
The ECM cant tell the difference between a open circuit and a short to ground.
They both produce 0v at the end of the circuit. Agree!
But checking for a short to ground is pretty easy.
Disconnect the battery.
Use your volt-ohm meter to probe each wire, checking for continuity to chassis ground.
If you follow the diagnostic instructions in the shop manual, you will also be directed to check continuity from the ECM harness connector to the sensor/solenoid connector.

Are the DTC's misleading?
one DTC says "short to ground", and the other says "open circuit". I read this to be two different issues.

OPEN CIRCUIT

SHORT TO GROUND

flash7210 · **Posted:** Wed Jun 24, 2020 6:59 pm

Quote:

Are the DTC's misleading?

Yeah, kinda.

a short to ground can be the same as a open circuit

and

sensor voltage low = high resistance = possible open circuit

racertracer · **Posted:** Sun Jun 28, 2020 6:57 am

So yesterday, I continued to search for “short to ground” conditions around the engine compartment and wire brushed and cleaned all the ground connections that I could find. I then tried to start it and noticed that the little red security light was on the dash that wasn't there before. I tried to clear it with the Harbor freight scanner https://www.harborfreight.com/automotiv ... 63806.html, and it didn’t go away. Besides the red security light being on, the scanner recorded many more codes that were not present prior.

It began to rain so I quickly closed the hood and decided to come back another day to document the codes and try again. I recall one code was water in fuel which I thought was strange.

I remember reading somewhere that if the security light is on the dash then I can forget about getting it started on my own, I will need the stealer to get involved with his OBDII code reader.

Any advice on how to proceed?

flash7210 · **Posted:** Sun Jun 28, 2020 8:04 am

Check the ASD fuse and ASD relay again

racertracer · **Posted:** Mon Jun 29, 2020 9:35 pm

fuses are OK.

Do you think it could be the ECM?

Engine turns over but fails to start.

flash7210 · **Posted:** Mon Jun 29, 2020 9:41 pm

If it’s a problem with the key or SKIM, a code should be set.

Scan for codes.

Help - My CRD died on highway traveling 45 to 50 mph

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