Firstly, I’m new to the Duramax this is the first one I have owned. Anyhow, recently the ole girl and I made a trip. On my way back the gauge cluster started to flutter and do a couple weird things. Fast forward, I want to say I have checked and verified all of my fuses are in working order and batteries are at good voltage and connections are tight. I have no fuel gauge, ECT gauge, Trans Temp, and my battery light stays lit. I have went through all the grounds as well and cleaned them. Here’s the weird thing, I have none of that or communication through the OBD2 port, I do have 12v to the obd2 port just no communication. I’m not sure entirely on what to do or where to begin tomorrow. Any help or direction would be appreciate.
Electrical Gremlins.
- Thread starter daltondurbin6
- Start date
You likely have some codes. Scan your truck and see what comes up.
I’ve been trying to. I cannot connect to read them. I have power to the OBD2 port, my scanner recognizes it, but won’t communicate with it.
01-02 or 03-04 truck? It matters.
01
Test pin 6 and 14 for voltage with key on an resistance between the two with key off. Voltage should be 2.5 +-2 on either leg (usually one is 2.7 and other is 2.3). Resistance should be 60ohm
Report back what you get
Report back what you get
Not on an 01.
I did test key on and off. Pin 16 was reading 12.8V. I do not have a pin 6, I have pin 2, 4, 5 and 14. At 14 I’m dead on voltage, Pin 2 from my understanding is your datalink pin and I was reading 3.4V. 5&6 from my understanding are your grounds of sort.
Key off, do you get resistance with one lead in pin 2 and other on ground?
Ohm wise Pin 2 and ground I got about .4 back with key off.
Should be open. Start unplugging modules till comms comeback or resistance goes away. You have a short to ground on the data line
Looks like the data link connector is the purple? Earlier today I unplugged the ECM, PCM, and batteries for like a half hour. It being my only source of transportation I just took it to town. Nearly home everything came back for a brief maybe 2 mins and then it went ghost again.Should be open. Start unplugging modules till comms comeback or resistance goes away. You have a short to ground on the data line
I googled it a bit, but my only question is would that cause my cluster and stuff to act up aswell?Should be open. Start unplugging modules till comms comeback or resistance goes away. You have a short to ground on the data line
Poor pin fittment
Thats not doing what i stated to do. You completely unplug one module at a time and retest resistance as i stated before. If no change, plug it back in and do the next one. If it goes open, theres your issue. Plug the scanner in and see if you can now communicate with other modules
I know on my '01 the gauge cluster is wired from the sensors. Which is why oil pressure sensors, and coolant temp sensors are different on the '01, but the same on '02 - 04' (and probably other years). Same as the power windows.