Rockdrummer93 Posted October 28, 2018 Posted October 28, 2018 I've done some searching with no luck. I have the 22 gallon dodge Dakota tank in my 87/98 Comanche. I am also using the Dakota pump and sending unit. Has anyone here figured out how to get the Dakota sending unit to talk to the Cherokee computer? or is there another pump/sending unit that will work in the Dakota tank that will talk to the Cherokee computer? My Comanche is about to hit the road here soon and I am wanting the gas gauge to work when that day comes.
HOrnbrod Posted October 28, 2018 Posted October 28, 2018 The fuel sending unit doesn't communicate with the computer. It sends a varying voltage based on the position of the float directly to the fuel gauge. The voltage polarity also has to be the same as the Jeep fuel gauge so the gauge indicates correctly. Do you know what the resistance of the potentiometer on the Dakota sender is from empty to full? Easy enough to check with an ohmmeter.
krustyballer16 Posted October 29, 2018 Posted October 29, 2018 Saveeveryjeep and I were just talking about this last night as we were going thru all his sending units.There has to be a sending unit that will work! Sent from my SM-G892A using Tapatalk
DirtyComanche Posted October 29, 2018 Posted October 29, 2018 4 hours ago, HOrnbrod said: The fuel sending unit doesn't communicate with the computer. It sends a varying voltage based on the position of the float directly to the fuel gauge. The voltage polarity also has to be the same as the Jeep fuel gauge so the gauge indicates correctly. Do you know what the resistance of the potentiometer on the Dakota sender is from empty to full? Easy enough to check with an ohmmeter. It should be a 220-20 ohm sender with 220 being empty and 20 being full. Stupid Chrysler standard. And being a stupid standard is the issue, as all Chrysler basket style pump/sender assemblies use that resistance range. You could probably send it to a rebuilder and have them put a different potentionmeter in it, or do it yourself. Otherwise you're stuck getting an aftermarket gauge, or going to the new style cluster, or you could possibly find a boat style capacitance sending unit that would produce a suitable output like the GM standard (0-99ohms) which would work reasonably well with a Renix gauge. Boat style ones install pretty easily in a plastic tank.
Dzimm Posted October 29, 2018 Posted October 29, 2018 Here are the wiring diagrams for the XJ plug (top picture) and the Dakota pump plug (bottom picture). Just cut and splice or make an adapter so you can retain the plugs for easy removal. No need to change the gauge or reprogram anything, it's plug and play. I made an adapter with a Mopar harness pigtail designed for a Dakota and an XJ fuel pump wire pigtail I cut off a spare XJ pump.
Dzimm Posted October 29, 2018 Posted October 29, 2018 Also as an FYI, these adapters on ebay have the correct plugs on each end but the wires go to the wrong pins. You can always buy one of these and cut the wires in the middle and reattach in the correct spots. https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F302893161216
DirtyComanche Posted October 29, 2018 Posted October 29, 2018 Does he have a 97+ cluster? Because that's what I would call relevant information for the OP.
Dzimm Posted October 29, 2018 Posted October 29, 2018 1 minute ago, DirtyComanche said: Does he have a 97+ cluster? Because that's what I would call relevant information for the OP. Yeah. His truck is a full 97+ swap.
HOrnbrod Posted October 29, 2018 Posted October 29, 2018 3 minutes ago, Dzimm said: Also as an FYI, these adapters on ebay have the correct plugs on each end but the wires go to the wrong pins. You can always buy one of these and cut the wires in the middle and reattach in the correct spots. No need to cut and splice. Use the correct pin extractor tool to rearrange the pins in the connector(s).
Dzimm Posted October 29, 2018 Posted October 29, 2018 Just now, HOrnbrod said: No need to cut and splice. Use the correct pin extractor tool to rearrange the pins in the connector(s). This is a better solution. Tool is cheap, but I'm cheaper than the tool
DirtyComanche Posted October 29, 2018 Posted October 29, 2018 3 minutes ago, Dzimm said: Yeah. His truck is a full 97+ swap. Alright. I stand by my comment that the Chrysler sending unit resistance range is stupid. Disregard everything else.
HOrnbrod Posted October 29, 2018 Posted October 29, 2018 2 minutes ago, DirtyComanche said: Alright. I stand by my comment that the Chrysler sending unit resistance range is stupid. Disregard everything else. Disregarded. It's only a stupid resistance range if you are a Mopar hater, which you obviously are.
DirtyComanche Posted October 29, 2018 Posted October 29, 2018 15 minutes ago, HOrnbrod said: Disregarded. It's only a stupid resistance range if you are a Mopar hater, which you obviously are. It's stupid because they changed it. Multiple times. It's only that standard once they went to plastic tanks with basket pump/senders. GM is the only one that really makes sense. 0-99 (100 effectively) ohms. With 0 being 0. That's like the metric system! Ah, well, 'Mericans would hate that, way too logical.
HOrnbrod Posted October 29, 2018 Posted October 29, 2018 1 hour ago, DirtyComanche said: It's stupid because they changed it. Multiple times. It's only that standard once they went to plastic tanks with basket pump/senders. GM is the only one that really makes sense. 0-99 (100 effectively) ohms. With 0 being 0. That's like the metric system! Ah, well, 'Mericans would hate that, way too logical. Ah, well, now you're bashing the USA too.
Rockdrummer93 Posted October 29, 2018 Author Posted October 29, 2018 So what y’all are saying is that once Chrysler went to the plastic tank and basket sender pump unit the resistance was the same? Therefore the Jeep 97+ plastic tank and unit and the plastic tank and unit from the Dakota tank should work hand in hand? If that’s true then I either may have something hooked up wrong or a band sending unit in the first place.Sent from my iPhone using Tapatalk
Dzimm Posted October 30, 2018 Posted October 30, 2018 13 hours ago, Rockdrummer93 said: So what y’all are saying is that once Chrysler went to the plastic tank and basket sender pump unit the resistance was the same? Therefore the Jeep 97+ plastic tank and unit and the plastic tank and unit from the Dakota tank should work hand in hand? If that’s true then I either may have something hooked up wrong or a band sending unit in the first place. Sent from my iPhone using Tapatalk Correct. The sending units operate the same way (at least I've yet to come across a Dakota unit that was different, what year is yours?). If you correct where each wires go using the diagrams above, it should work.
Rockdrummer93 Posted October 30, 2018 Author Posted October 30, 2018 I'll have to look at the way I have it wired. I'm almost certain its hooked up right. I am suppose to be dropping it off Thursday for exhaust work. Once I get it back I'll drop the tank and figure it out.
Rockdrummer93 Posted November 4, 2018 Author Posted November 4, 2018 Just dropped the tank ran some tests and ran some tests. Turns out I was missing a ground. Works as it should now thanks for the help Sent from my iPhone using Tapatalk
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now