Wow what big exhaust tip I have
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The 4.2 doesn't have the battery monitor, so it isn't an issue.
I don't know for sure what effect bypassing the monitor on a 5.0 will have. My guess would be: the monitor will underestimate the charge in the battery, so it will tend to trigger 'low battery' messages to the rest of the car's modules, and probably trigger diagnostic codes.
However, if the charge is only a trickle, the level of underestimation may be pretty small. And while Jag says that you may get some issues, I don't think I've seen anyone report codes related to battery warnings. And I've connected a charger direct to the battery (before I learned about this) with no problems. On the other hand, I know that the ECM will shut down 'non-essential' services if the battery monitor reports a low charge, and that might possibly explain some of the weird electrical gremlins that occur despite people using battery maintainers.
Bottom line: since Jaguar says "Connect to +ve terminal and a chassis ground", that's what I'll be doing in future. It isn't really more difficult than connecting both leads to the battery.
I don't know for sure what effect bypassing the monitor on a 5.0 will have. My guess would be: the monitor will underestimate the charge in the battery, so it will tend to trigger 'low battery' messages to the rest of the car's modules, and probably trigger diagnostic codes.
However, if the charge is only a trickle, the level of underestimation may be pretty small. And while Jag says that you may get some issues, I don't think I've seen anyone report codes related to battery warnings. And I've connected a charger direct to the battery (before I learned about this) with no problems. On the other hand, I know that the ECM will shut down 'non-essential' services if the battery monitor reports a low charge, and that might possibly explain some of the weird electrical gremlins that occur despite people using battery maintainers.
Bottom line: since Jaguar says "Connect to +ve terminal and a chassis ground", that's what I'll be doing in future. It isn't really more difficult than connecting both leads to the battery.
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From: London, UK
Sorry, Richard, I wasn't recommending the Jag product, just quoting what they said. I agree - stupid to pay big $$$ for a Jaguar sticker. I assume it comes with a 12V lighter socket that you fit next to the battery simply because the OEM charger only comes with a lighter plug. Sounds a bit kludgy to me.
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From: Florida
The 4.2 doesn't have the battery monitor, so it isn't an issue.
I don't know for sure what effect bypassing the monitor on a 5.0 will have. My guess would be: the monitor will underestimate the charge in the battery, so it will tend to trigger 'low battery' messages to the rest of the car's modules, and probably trigger diagnostic codes.
However, if the charge is only a trickle, the level of underestimation may be pretty small. And while Jag says that you may get some issues, I don't think I've seen anyone report codes related to battery warnings. And I've connected a charger direct to the battery (before I learned about this) with no problems. On the other hand, I know that the ECM will shut down 'non-essential' services if the battery monitor reports a low charge, and that might possibly explain some of the weird electrical gremlins that occur despite people using battery maintainers.
Bottom line: since Jaguar says "Connect to +ve terminal and a chassis ground", that's what I'll be doing in future. It isn't really more difficult than connecting both leads to the battery.
I don't know for sure what effect bypassing the monitor on a 5.0 will have. My guess would be: the monitor will underestimate the charge in the battery, so it will tend to trigger 'low battery' messages to the rest of the car's modules, and probably trigger diagnostic codes.
However, if the charge is only a trickle, the level of underestimation may be pretty small. And while Jag says that you may get some issues, I don't think I've seen anyone report codes related to battery warnings. And I've connected a charger direct to the battery (before I learned about this) with no problems. On the other hand, I know that the ECM will shut down 'non-essential' services if the battery monitor reports a low charge, and that might possibly explain some of the weird electrical gremlins that occur despite people using battery maintainers.
Bottom line: since Jaguar says "Connect to +ve terminal and a chassis ground", that's what I'll be doing in future. It isn't really more difficult than connecting both leads to the battery.
Is there an exact chassis ground location in the trunk they recommend to place the negative lead of the charger? I would consider making the change if I can use the existing charger negative lead without making any significant modifications. Has anyone used this trunk ground and have pictures?
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They didn't recommend a specific one, and I'm afraid I haven't needed to connect a charger since I learned about this, so I haven't had to find a point to connect to. But I recall seeing some grounding points when I last looked - just can't recall the details.
Last edited by Ngarara; May 4, 2014 at 06:15 AM. Reason: Speeling misteak
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From: CA
I have a 5.0 car with the battery monitor and have the charger connected to both battery terminals with no issues so far. Should I be changing the negative connection to a ground in the trunk area or can I get by? Will I be looking at any problems down the road with my present hook up?
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