P0500 code

[ericlouie1]

I was getting the abs module open relay code, so I sent the ABS module out to circiutboardmedics to have it "rebuilt"(not 100% sure what this service entailed)
Anyways, before I sent the module out, I had a constantly lit brake light, as well as a working speedo.
I received the module today, and thinking everything was honkeydorey, plugged it in, all was well for about 1 minute, then the gauges temporarily died, I got the check engine light and brake light(p0500, p1693 and p1694 codes when pulled with the 3xkey trick)
The rest of the gauges came immediatly back, except for the speedo.
The driver side wheelhub was just replaced with a new skf unit and sensor. The p/s hub and sensor looks like it was replaced before i purchased the truck.
ABS fuse in cab is good, and 40A fuse in engine bay looks good as well.
I checked the resistance of all the wheel sensors, as well as a check to ground for each wire, no continuity to ground on any of the sensors.
The resistances from plug at ABS module to sensor looks like this-
D/S front sensor 1.03k ohm
P/S front sensor 1.06k ohm
Rear wheel sensor 1.7K ohm

I also checked voltages from the plug to ground, but they seem kind of pointless, considering I don't have a schematic/pinout of the plug handy.
Anyone have any input on this one, I'm going to contact the vendor in the AM to see what they say.

The truck in question is a 2001 RCLB 4x4 HO 5.9 6 speed 103,000 on the odometer

[Mopar1973Man]

Here is the wiring diagram...

(attachment below)

As for sensors. I will say if you still having issues I'm going to bet its like myself its going one of the front sensors is mismatched and causing the ABS / BRAKE light issues. As for the error codes that is CCD network bus error.

antilock brakes.pdf

[ericlouie1]

My big question is that before I sent the module out I had a speedo, but the brake light was on, after I got it back, now I have no speedo, and still have the brake light on....it got worse!

[Mopar1973Man]

If you have a warranty I would send it back or contact them and talk to them and explain the problem.

Like mine I just got my module back from "Module Masters" and still had the same problem yet. Come to find out the wanted me to clean the sockets and makes sure the connectors what making good contact. I was using di-electric grease in the plugs. So I clean them out and now found I was getting a consistent issues of pulling right. So I replaced my right sensor with a another used sensor and it went away. 

So what you'll need to do is get a code reader. Now reset the codes and see what comes up after restarting. Is in the same codes? Now unplug the ABS module (both plugs) and now reset the codes again. Now test it again do the codes return or not? I know either case the speedometer will not function till the CCD network issue is resolved.

[ericlouie1]

Yeah, I jsut cleaned all the connectors the best i could(no contact cleaner with me) and re-greased them with fresh dielectric. Going to go out now and see if it made a difference.

Worst comes to worse I'll unplug all the abs stuff and just stick a portable GPS unit in front of my speedo....stupid chrysler and their stupid technology. LOL!

[ericlouie1]

So after disconnecting everything, light cleaning, regreasing i pulled the truck out of the shop...no lights, speedo seems to be working...start driving up the street and I get to about 15 mph, airbag light comes on, speedo drops out, check engine light comes back on, and so does the brake light.

Back to square 1.

[Mopar1973Man]

I would leave it unhooked and see if the module is causing the problems or not. If the ABS module is having troubles and shorting out the CCD network then the rest will crash as long as it's hooked up but if you unhook it and everything works then the module should be returned for warranty service.

[Me78569]

I would be looking at the abs computer again, have the people refix it.

[ericlouie1]

Yeah, once the abs module is unhooked the brake light goes out, as does the "bus" errors/check engine light, but no speedo. I am thinking that the abs light in this truck is burned out, as I do not ever recall seeing it turned on.

[ericlouie1]

Drove it this morning to work, speedo lasted about 5 minutes before airbag light came, dash did the goofy dance, and lost the speedo.....but no brake light, just a CEL and a lack of speedo.

[Mopar1973Man]

I'm going out on a limb to learn more about these ABS issues.

 

Edited December 9, 2015 by Mopar1973Man

[ericlouie1]

I was able to intermittantly communicate with the abs module with a snap on solus, until the air bag light lit, odometer dropped out, and the CEL came on.

Voltages at abs connector(disconnected) seem fine, 12V for all fused inputs, 2.5V for CCD bus, and 5V for the speed signal reference.

This is what I have done so far.

I pulled all of the ECU, PCM and ground connectors under the hood and checked for corrosion and gave them a light coat of dielectric.

Removed grounds from frame, battery to body, random one at rad support, one at d/s firewall going into the cab, pcm to body, sanded paint off of body/frame, cleaned ring terminal, new screws, and a small coat of grease. All points between grounds is about .3 ohms.

Contact cleaned the connectors going into the abs module, and tried them dry, really didn't make any difference, the longest I can communicate with the module is for about 3 minutes. During this time, I am able to look at the data display, activate the pump through the scan tool, and look at any codes(none present)

I can re-establish communication after about 5 minutes of sitting and clearing the CEL, or by disconnecting the ABS module, then reconnecting.

I did determine that at least one of the batteries is bad, there was resistance between the negative terminal and body ground of about 5 ohms. This would climb to around 20 ohms when a door was opened. Put a brand new battery in and the resistance dropped to 2 ohms, climbing to 8 ohms when the door is opened. Thats a strange one for sure.

With the abs module disconnected, no CEL, or other errors occur.

This sure is an interesting one.

BTW, CEL's thrown are P1693 and P1698, not much info there though.

 

[Mopar1973Man]

Ok.

The CCD voltages look close to correct with open plug. 2.51 and 2.49 is normal. Your darn close to that!

As for the Rear speed sensor that should be OHMs about 1.7k ohms. now if you set for AC volts you spin the rear axle the speed sensor should create a small amount of AC voltage. About 0.2 AC volts. It actually frequency you should be looking with a O-scope.

 

[ericlouie1]

All of the sensor ohms were read full loop, from the connector to the sensors.

All of this testing was performed with the truck sitting, not even driving it.

Before I sent the module out I had the internal relay code, the fuse pulled, had the brake light on, but still had a speedo. Now I have no speedo, CEL's, but no brake light....confusing.

I want to get the module interface issues sorted out before I start messing with the drivability end of it. No o-scope is available to me right now anyways, so its a moot point currently. Although I do have a analog simpson meter that I might be able to use for that particular test.

 

[ericlouie1]

Module was sent back last friday, I'll keep updating as I go along.

[Vais01]

Well from my knowledge you can set a 0500 by mismatched wheel spin. So if your driving and your front tires are going slower than the rears you can set that code. 

Excessively oversized rear tires and factory sized tires in the front could also be a culprit.

[dripley]

You can spin the rear tire on wet pavement and do that. I have.

[ericlouie1]

The p0500 was set on dry asphault, with no wheelspin, hard braking, or hooliganism.

Just thought I would give an update to this, I got a phone call from circuitboardmedics on thursay, notifying me that the module was shipping back to me. The guy on the phone wasn't a technician, he just explained that they found something wrong with it that they typically don't see. It also took a bit of time to trigger the faqult on their test bench. I received the abs module back saturday, plugged it in, and voila, no lights, speedo is back, and odometer works again. Put about 130 miles on it between then and now, and all seems good.

[Vais01]

On Monday, December 21, 2015 at 8:24 PM, ericlouie1 said:

The p0500 was set on dry asphault, with no wheelspin, hard braking, or hooliganism.

Just thought I would give an update to this, I got a phone call from circuitboardmedics on thursay, notifying me that the module was shipping back to me. The guy on the phone wasn't a technician, he just explained that they found something wrong with it that they typically don't see. It also took a bit of time to trigger the faqult on their test bench. I received the abs module back saturday, plugged it in, and voila, no lights, speedo is back, and odometer works again. Put about 130 miles on it between then and now, and all seems good.

Great to know. Glad you got it fixed up. 

[dripley]

That is good to hear. Always good to see the solution works.