What we know:1. remote diagnosis is difficult at best ;)2. not having a sc
hematic makes that worse3. the resting voltage of an EarthX is about 13.2 V
Questions:1. have you put the voltmeter across the input and output studs o
f the solenoid?=C2- With what you are describing, engine off, that readin
g should be 0.6 volts (13.2 in - 12.6 out = 0.6 volts)
2. does cranking current flow thru this solenoid?
3. has cranking seemed "soft" lately?
3. is there an errant diode somewhere in the circuit - just a WAG, but 0.6
v is about the drop of a silicon diode - again, just making this up ;)
Things you could try:Starting with simple, no-disassembly-required tests1.
put the voltmeter across the input and output studs with everything off - w
hat's that voltage?2. turn on the master (but don't run the engine) - based
on your description, should read 0.6v3. start turning on high-current stuf
f like pitot heat, landing lights, etc - IF there is some weird resistance
thru the main contacts, the voltage drop should increase as you add load.
=C2- If you have an ammeter, write down amps, what equipment is turned on
, and voltage drop across solenoid.
You could have a high-resistance thru the contactor, but if starting is goo
d, it kinda rules that out.
Also, the resistance we are talking about would be well below 1 ohm and typ
ical multi-meters cannot accurately measure resistances that low.=C2- Jus
t as JoeG mentioned, you will have to use another technique to test that hy
pothesis.=C2- #3 in Things to Try might shed some light on this.
Happy (gremlin) Hunting,
-Jeff
On Monday, December 1, 2025 at 03:50:03 PM PST, bobnoffs <icubob@gmail.
com> wrote:
voltage at eis is 12.6 with engine off. it is 14.3 with engine running. i h
ave checked all numbers with eis voltage, handheld voltmeter and panel moun
ted voltmeter i just bought and they are all aligned.. measured voltage is
13.2 at battery side of solenoid and 12.6 on the load side, engine off.=C2
- alternator is charging fine and battery voltage is fine but after the s
olenoid it drops to 12.6. all this is with an earthx, not lead acid.
i haven't actually measured resistance in the solenoid but it seems to be
pointing at that, what else could it be?
bob
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=516709#516709
-
S -
WIKI -
-
=C2- =C2- =C2- =C2- =C2- -Matt Dralle, List Admin.
