Clamp-on amp meters are generally designed to measure AC current. There are ways to use them with DC, but you usually need pretty fancy kit for the measurements to be reliable, especially with low-amp measurements. You should disconnect the positive terminal of the battery and run the current through a multimeter using the leads on at least a 10A setting. There is sometimes a different lead plug on the meter for this, and check that the internal fuse isn't blown. They often are, and it will blow for sure if you try to start or possibly even turn the vehicle on.
Parasitic Draw
- Thread starter avslash
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avslash
Full Access Member
I like your toggle switch idea.
I have a NOCO charger under the hood and a male plug mounted in the bumper to power it. I just ran the output to the aux battery though based on Traxides assertion that when one battery is charged both will lb charged automatically.
I have a NOCO charger under the hood and a male plug mounted in the bumper to power it. I just ran the output to the aux battery though based on Traxides assertion that when one battery is charged both will lb charged automatically.
I have never quite understood that, or more correctly, when all is parked, that the Traxide allows power to go both ways regardless of the voltage condition of the other battery.
I say that as one of the "benefits" of the Traxide design is that it does not allow one battery to discharge the other and hence the question does it allow one battery to charge the other without discharging the first battery?
Since I did not know the answer, and was afraid of joining the two battery's together with 14 gauge wire and a few fuses, hence the toggle switch and I know the battery's are separated during the trickle charge, as that is what it is.
blake aiken
Well-Known Member
Ive recently started having a new ground fault/open circuit issue - car shut off twice while on the road and fired back up. It didn’t store a fault when it **** down but while scanning it back home I got a starter circuit fault. It’s forced me to finally learn electrical diagnostics which I’m not a fan of at all. I bought a multimeter to check fuses but it seems tedious and from what I’m finding online it seems like the amp draw is going to be intermittent making this an even more difficult goose chase. I’m a visual person so I picked up a flir one pro off eBay to add to my tool bag and I’m hoping this will help me hone in on issues much faster.
This is the engine compartment fuse box, r6 for the engine electrical system. It’s not in sleep mode here so it could be normal draw.
Engine fuse box while running
This is the box in the lower dash, not sure what relay this is but it’s hot.
This is the engine compartment fuse box, r6 for the engine electrical system. It’s not in sleep mode here so it could be normal draw.
Engine fuse box while running
This is the box in the lower dash, not sure what relay this is but it’s hot.
Relay R1 per the jpg below on my LR3 seems to power the auxiliary power sockets as opposed to the cigarette light sockets - all look the same of course.
The jpg shows the relay removed and a jumper installed. This is so that my aux sockets remain powered all the time. This means that if there was something plugged into the sockets, the something would be powered as long as their was juice in the cranking battery.
What else that relay circuit powers, I do not know.
The jpg shows the relay removed and a jumper installed. This is so that my aux sockets remain powered all the time. This means that if there was something plugged into the sockets, the something would be powered as long as their was juice in the cranking battery.
What else that relay circuit powers, I do not know.
Michael Gain
Full Access Member
I'm pretty sure that R6 is the starter relay. Lead to the starter may be grounded somewhere..
I note the comment about the scanner calling up some starter fault.
The trouble with all these scanners is I find they generally send you off in the wrong direction. I know that is not nice to say but what you can learn from these scanners is that if you are patient and can get them to tell you a series of differing errors, then often you can figure out the common element.
It you had a starter problem, I tend to think the engine would not start or there would be the clicking thing a number of times before the engine did start. Once the engine is going however, it will keep going and you will be afraid to shut it down - you will not when at the grocery store etc but will leave it running, hope it is still there when you return and if so, at least it will get you back home.
The jpg's below show or attempt to show the starter solenoid contacts that tend to fail and hence either a new solenoid or more commonly, a new starter motor.
Are you getting any odd fluctuations of the gauges on the instrument panel? Fuel or temperature gauges intermittent - that sort of thing.
I ask as there is a single large connector on the rear inboard side of the instrument cluster that feeds not only the gauges but the backup memory chip for the engine computer. The plug tends to loosen in the connector over the years as LR did not make the cable quite long enough and it is always being tugged at. The fix is just to unplug and replug the connector. The clue is that the gauges tend to act odd or just not read.
Getting to the rear of the instrument cluster is not so easy but once there, the unplug / replug thing is easy.
I mention this as that not quite connectoed connector can be a real show stopper, as in there is nothing - no lights etc - like the battery has been removed - everything is dead - well maybe the interior lights work but that is about all.
The 3 basically will not run without the backup memory chip and that is also the reason you cannot swap instrument clusters with another similar vehicle - the VINs must match.
The link below to how to remove the instrument cluster on a Sport - the 3 is similar and I expect there are YouTube videos specific to the 3.
The doc attached talks about the instrument cluster and the CCF, Car Configuration File and how the chip within the cluster must communicate with the Engine Control Module and the Central Junction Box - this is a real committee affair but must be 3 out of 3, not 2 out of 3 as is often how this stuff works - like say when guys rocket off to the moon.
The trouble with all these scanners is I find they generally send you off in the wrong direction. I know that is not nice to say but what you can learn from these scanners is that if you are patient and can get them to tell you a series of differing errors, then often you can figure out the common element.
It you had a starter problem, I tend to think the engine would not start or there would be the clicking thing a number of times before the engine did start. Once the engine is going however, it will keep going and you will be afraid to shut it down - you will not when at the grocery store etc but will leave it running, hope it is still there when you return and if so, at least it will get you back home.
The jpg's below show or attempt to show the starter solenoid contacts that tend to fail and hence either a new solenoid or more commonly, a new starter motor.
Are you getting any odd fluctuations of the gauges on the instrument panel? Fuel or temperature gauges intermittent - that sort of thing.
I ask as there is a single large connector on the rear inboard side of the instrument cluster that feeds not only the gauges but the backup memory chip for the engine computer. The plug tends to loosen in the connector over the years as LR did not make the cable quite long enough and it is always being tugged at. The fix is just to unplug and replug the connector. The clue is that the gauges tend to act odd or just not read.
Getting to the rear of the instrument cluster is not so easy but once there, the unplug / replug thing is easy.
I mention this as that not quite connectoed connector can be a real show stopper, as in there is nothing - no lights etc - like the battery has been removed - everything is dead - well maybe the interior lights work but that is about all.
The 3 basically will not run without the backup memory chip and that is also the reason you cannot swap instrument clusters with another similar vehicle - the VINs must match.
The link below to how to remove the instrument cluster on a Sport - the 3 is similar and I expect there are YouTube videos specific to the 3.
The doc attached talks about the instrument cluster and the CCF, Car Configuration File and how the chip within the cluster must communicate with the Engine Control Module and the Central Junction Box - this is a real committee affair but must be 3 out of 3, not 2 out of 3 as is often how this stuff works - like say when guys rocket off to the moon.
blake aiken
Well-Known Member
Im gonna get under there and remove the panels and check for hot spots soonish. Electrical stuff is seriously not intuitive, it’s been cool using the thermal imaging to understand it visually.
Bbyer
Wow, I’m gonna need to reread your post a couple more times. When I wrapped up my timing chain overhaul the starter started firing off when I reattached the battery. I replaced it with a used unit. I’ll investigate the aux plugs soonish. I’ve got a rain sensor code and bcm needs calibration codes as well with the gap tool.
Thanks guys
Also, if anyone’s interested in the flir I got it from a seller on eBay, they auto accepted a $275 offer. Really good deal if you want to explore thermal.
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