R
Rbike
Guest
The problem is no spark on a 1976 R75/6 that is modified for dual plugs with a Dyna ignition system and has been sitting for a while.
Here is what I found:
The pickup has a red and a white wire that run to the module:
Red wire has 8.9VDC with the key on and 8.0VDC while cranking
White wire changes from approx 1.4VDC to .8VDC while cranking
The coils:
Labled 1.5 ohms but each measures 2.8 ohms individually.
Green wire that looks like it comes from the original harness has 10.6VDC and is hooked to coil one and is jumpered to a red wire going to the module. Powered when the key is turned on.
Black wire from coil one to coil two has 6.25VDC at coil one and 6.0VDC at coil two.
Brown wire from coil two going to the module changes from 1.4VDC to 10VDC when cranking.
Module:
Also has a black wire going to ground that I verified to have no voltage drop when compared to the battery ground, and to show good continuity.
Battery:
12.2VDC
SO...it looks to me as though the pickup is changing state and sending a signal to the module. Then it seems as though the module is controlling the grounding of the coils by controlling the Brown wire. But I am wondering if the 1.4VDC that I measure as the low on the Brown wire is indicating that the module is not providing a good ground. Or is the pickup not changing state correctly...even though the module seems to change state?
Please let me know if it is obvious why there is no spark, or if there is a test I can do to determine which part is bad...
Here is what I found:
The pickup has a red and a white wire that run to the module:
Red wire has 8.9VDC with the key on and 8.0VDC while cranking
White wire changes from approx 1.4VDC to .8VDC while cranking
The coils:
Labled 1.5 ohms but each measures 2.8 ohms individually.
Green wire that looks like it comes from the original harness has 10.6VDC and is hooked to coil one and is jumpered to a red wire going to the module. Powered when the key is turned on.
Black wire from coil one to coil two has 6.25VDC at coil one and 6.0VDC at coil two.
Brown wire from coil two going to the module changes from 1.4VDC to 10VDC when cranking.
Module:
Also has a black wire going to ground that I verified to have no voltage drop when compared to the battery ground, and to show good continuity.
Battery:
12.2VDC
SO...it looks to me as though the pickup is changing state and sending a signal to the module. Then it seems as though the module is controlling the grounding of the coils by controlling the Brown wire. But I am wondering if the 1.4VDC that I measure as the low on the Brown wire is indicating that the module is not providing a good ground. Or is the pickup not changing state correctly...even though the module seems to change state?
Please let me know if it is obvious why there is no spark, or if there is a test I can do to determine which part is bad...