Nut Scratcher E-450 Ambulance

the_twig_187 · September 2, 2015

today was a brutal electrical day that had me spinning right round baby, right round like a record baby.

2011 E-450 Ambulance comes in with door ajar light/ dome light on at all times and parking brake light on at all times. so I start by going into data logger to see which door is causing the ajar light. cannot communicate with the SJB. ppt "F" for no communication with SJB and conclude an internal fault within the SJB. replace the SJB and attempt to program. programing failed "can not communicate with the module. hum? load test power and 3 ground circuits in the SJB all test good. disconnect battery and test for resistance between pin 3 and 11 of the DLC, I get 60 ohms which is normal for the 120ohm terminal resistors that are wired in parallel in the circuit. then I test pin 3 and 11 for continuity between ground (short to ground) BOOM! I get 2.0ohms of continuity. so I have a short to ground on the med speed communication network circuit. ok so this is an ambulance, who knows what/where they have tapped into this connection.

so I notice they relocated the ACM (radio) from the dash to the cup holder section of the dog house cover. so I follow the network wires from the DLC and they go right into the doghouse. I unwrap a large section of electrical tape and I find it. they needed to extend the harness to have it reach down to the doghouse and the guy who did the conversion did a pretty good job. he soldered the connections and placed heat shrink tubing on the wires. problem was he didn't apply heat to the heat shrink tubing! he just slipped the tubes on and wrapped the hole thing in electrical tape. so over time the heat shrink wiggled down and then came in contact with the "unshielded" radio antenna "ground" wire. A short to ground on this network will cause erratic behaviour in modules but will not necessarily bring down the network.

this is more of a one-off concern but it had me spinning...helpful to know

lmorris · September 2, 2015

today was a brutal electrical day that had me spinning right round baby, right round like a record baby.

Thanks a lot.... :twack: Now I have that song stuck in my head.... :banghead:

ktmlew · September 2, 2015

today was a brutal electrical day that had me spinning right round baby, right round like a record baby.

Thanks a lot.... Now I have that song stuck in my head....

ktmlew · September 2, 2015

If I, I get to know your name Well if I, could trace your private number, baby All I know is that to me You look like you're lots of fun Open up your lovin' arms I want some, want some I set my sights on you (and no one else will do) And I, I've got to have my way now, baby All I know is that to me You look like you're having fun Open up your lovin' arms Watch out here I come You spin me right round, baby Right round like a record, baby Right round round round You spin me right round, baby Right round like a record, baby Right round round round I got to be your friend now, baby And I would like to move in just a little bit closer All I know is that to me You look like you're lots of fun Open up your lovin' arms Watch out, here I come You spin me right round, baby Right round like a record, baby Right round round round You spin me right round, baby Right round like a record, baby Right round round round I want your love I want your love All I know is that to me You look like you're lots of fun Open up your lovin' arms Watch out, here I come You spin me right round, baby Right round like a record, baby Right round round round You spin me right round, baby Right round like a record, baby Right round round round You spin me right round, baby Right round like a record, baby Right round round round You spin me right round, baby Right round like a record, baby Right round round round You spin me right round, baby Right round like a record, baby Right round round round You spin me right round, baby Right round like a record, baby Right round round round Read more: Dead Or Alive - You Spin Me Round Lyrics | MetroLyrics