3500 '08 Brake Light, ABS Light, Chime - every 30 - 40 seconds

[hwebster]

First - Hi Guys I'm back!! Been lucky for a while the truck has run well and few problems... until a few weeks ago.. Blew the power steering pump 40 miles from home and had to ride a flat deck home! Then I dropped a tie rod end and needed a 2nd tow.. Twice in less than a week, and it was the same Tow Truck Driver! Need to replace the clutch soon and then this morning...

Went to town and stopped for fuel. Pulling out of the station the Brake Light, ABS Light and the door Chime went off. Turned off, then 30 seconds later came back. Continued until I made my next stop. Checked the Parking Brake - not the problem. Checked the fluid levels - right up there, no problem. Started up after the last stop... same thing. Decided I didn't want to keep driving in that state so I headed home. No braking issues on the road and on the grid I locked her up to see if anything would show. Nope all good...

Reading the forum the most likely cause would be wiring? One post mentioned having a uni joint replaced and rubbing thru some wiring. given the new ball joints...Could be a cause and I'll check it tomorrow. Any other thoughts? Am I warm?

Glad to see the forum is still booming. Don't know when I made my last post but it was before the upgrade to this platform... Looks good!!

Thanks All Harrison!

 

[hwebster]

Crawled around under her this morning... No obvious breaks in the wiring that I can see... Might be internal to the drum? H

 

[bighammer]

I'm gonna guess it's a bulb in the rear. It seems like I remember multiple times having the same thing years ago. The bulbs looked fine and weren't burned out, (they even worked when I was parked and checked with the 4-ways) but it's the plastic base with heat and vibration that lets the contact wire embed in the plastic. Hit a bump, chime chime, bulb out.

I went to a local auto parts store and asked for replacements with an all glass base, no black plastic, end of problem.

 

[hwebster]

Thanks Big Hammer... Never would have though about the bulbs... I will check them all tomorrow.. it isn't -30!!!!

 

[hwebster]

Hmmm - So I checked all the lights - pulled them, cleaned em verified the connectors... but.. before I did that I went for a quick drive and no issue. I'm thinking it might be related to a crack somewhere in the circuit, where water is getting in. Been melting during the day here... spring is coming... so it's been really wet. Should be a real treat to troubleshoot... Rats...

 

[hwebster]

That was short lived, tried again this am and immediately after starting the lights and chime began to cycle... Gonna keep looking!!

 

[hwebster]

Well Sherlock... You really should have gotten down lower!!! Turns out there is a sensor on the rear differential with a nicely exposed connector and wires. Turns out the connector had been poorly treated by gravel... I live in Saskatchewan we have more dirt roads than any other province or state!! Go figure... Wires were corroded, sheathing cracked and the connector cracked as well. Whenever it got wet... Ring my Chime every 30 seconds... All gone now!!!