• Welcome to For E Bodies Only !

    We are a community of Plymouth Cuda and Dodge Challenger owners. Join now! Its Free!

Need help with wiring issues.

MyR/T

Well-Known Member
Joined
Mar 22, 2018
Messages
79
Reaction score
25
Hello everyone. Having a problem with dash wiring. New M and H harness from year one and guages gone through and restored by Auto Instruments. Finally put power to it today and it blew the bottom fuse for the Instrument cluster. The thing that stands out is that even with the blown fuse when the key is turned on the temp guage goes up and is buried past the H on the hot side of the guage. I'm going to retrace all the wires tomorrow but could use help on what could be the cause. One other thing i noticed was that the horn works when the key is off or turned back towards you but doesn't work when the key is in the on position. Car is not running yet , just trying to sort the electrical stuff out first. Thanks
 
Last edited:

Challenger RTA

Well-Known Member
Joined
Oct 28, 2018
Messages
2,813
Reaction score
1,408
Location
PA Flood city
Start by checking cluster gauge wiring.
Take note 12v in the voltage limiter 5v out.

1972_barracuda_rallye.jpg
 
Last edited:

MyR/T

Well-Known Member
Joined
Mar 22, 2018
Messages
79
Reaction score
25
I ran all the wires off the manual and everything seemed to match up. My 4speed reverse light was staying on all the time and i found that the wires were swapped in the bulkhead connector. They are both M and H so you never know. Going to recheck tomorrow . Thanks
 

Challenger RTA

Well-Known Member
Joined
Oct 28, 2018
Messages
2,813
Reaction score
1,408
Location
PA Flood city
You said :when the key is turned on the temp guage goes up and is buried past the H.I would suspect there connections on the rear of the cluster are wrong,or the voltage limiter is bad.
 

MyR/T

Well-Known Member
Joined
Mar 22, 2018
Messages
79
Reaction score
25
check #5 violet for a short or bad sending unit.

View attachment 102522
I double checked all wiring on guages , everything matches the service manual diagram. Have 12v to the limiter and it pulsates between 2 and 6 volts coming out. Has a red light that is flashing on the back. Checked all wires going into the bulkhead and everything matches up. How can I test the temp sending unit?
 

EW1BH27

Well-Known Member
Joined
Dec 31, 2021
Messages
487
Reaction score
220
Location
Canada
How can I test the temp sending unit?
Check out "My contribution..." in Reply#1 on another forum. Resistance was measured at room temperature and boiling water (212*F). Reminder, I threw the the one in the first pair of pics The second pair is the one out of my car.

 
Last edited:

MyR/T

Well-Known Member
Joined
Mar 22, 2018
Messages
79
Reaction score
25
I'm going to call Auto Instruments in the morning and see what they have to say. I'm at a loss as to what could be wrong. Thanks for all the replies, I really appreciate the help.
 

MyR/T

Well-Known Member
Joined
Mar 22, 2018
Messages
79
Reaction score
25
I got the guage fixed. Turns out the guage was grounding itself out against the housing. I loosened it , adjusted it a little, and tighten it back up. Now it works like it should. Thanks everyone.
 
Back
Top