Since this is convoluted. and need multiple 12v source options for each item since some may be disconnected by conversion.... thusly am starting own thread.
photo's are my under hood box and cover. (2002... or is it 03. I forget) Will post this first then come back and add pictures
Anyway. Here goes. Ohhh. and to confuse things from get go:
A. This Jeep was converted to a diesel by previous owner. Their grafting of Mercedes Glow Plug wiring into the Jeep system worked. Dash Worked except Tach. I am swapping this clapped out engine for a rebuilt one of same kind/model mercedes. Started in Nov. but got to cold. Restarted project when retired in June.
B. there is no CPS (crank position sensor) it is cut off. Previously it worked sorta. CPS was there but just dangling off to the side and not on the Jeep Transmission. I cut it off since it just jangle dangled by the hot exhaust. Can reconnect if it needs it to make the computer happy (or jumper it ... suggestion how?) Computer only gives me dash stuff except Tach.
First-. embarrassed to say do not know how many key positions there are on the TJ. Actually searched the inter-webs but didn't find it.... is there even an accessory? Ill Include it just in case. For lack of not knowing the TJ world Terms will use:
. SC (Start/Crank),
. RD (Run Driving),
. Asc (Accessories operate in keyed Asc. position, when engine is not running, but NOT when key is off) ,
. Off (off- key in or out)
Second/Third. Don't care if tap into a Fuse slot or remove an unused relay and tap slot(s) there. Do not need to go thru a Jeep fuse. Do not Want to piggy back on a functioning relay such as there is a fuel pump relay in Power box still. Do not know why; there was no 12v pump in conversion. Was it there to keep computer happy? Previous builder just left it as a spare? he was lazy??. I could remove it and tap something there??
Four- I am adding some fuel pump(s) this time though... again it had no elec. fuel pump in previous running diesel conversion arrangement. Engine has a mechanical lift pump. I could; if it would still keep computer happy, remove Jeep fuel pump relay and use one of its slots as a Tap in point... or off its fuse home???
Five- All the timers I speak of below have a relay built in.
Six- the two timer's i am adding do NOT need positive power in key off position to keep memory of their settings (supposedly). Chinese directions hard to decipher butt other's seem to report that this is the case.
Seven- BTW: Am putting a separate inline-fuse for each below so only 12v positive (or negative?) is needed at the right Key switch position(s) for each device below:
Device One- (Mercedes glow plug relay / diesel swap). PRIORITY. NEED THIS NOW. It has two hot wires. I would wire this back like it was. butttt. the so called PERMANENT ink faded on my labels and I can no longer read them. Thought I had pictures. but nooo. (did I say Im stupid to have thought double redundancy would be enough)
1. Wire ONE is to be wired to +12v at key RD position- assuming RD is prior to SC in key position like it always is duhhh. In normal use; this MB relay.... with key in position to power it; its own internal timer does it's Glow hot plug thing. At chime. you move key to SC to start the engine or I can push a button to have it start the timer again on extra cold days that I want to glow the plugs twice. It's internal timer will switch off relay depowering the Glow Plugs.....if I understand correctly how this works there is more to it (there is thermal switch in there too). Do NOT want this powered in Asc key position or Off position.
2. Wire TWO provides 12v during SC . This delay's (skips past?) the timer. Timer resumes after engine starts (if any time left) and key is back to RD. Likely OEM mercedes did this way cause all their other items switched off during crank to leave battery only getting draw from starter and glow plugs???. Do NOT want this powered 12v in Asc key position (jamming to tunes looking at a sun setting atop a mountain) or Off key position.
3. It has a ground wire but mercedes did not use that as a switchable thang.
Device Two- Inline Electric Primer lift pump / Emergency drive lift pump. Same pump for either. Once best power source found based on below , power will first go to a timer I can program. In normal use this likely will only be set to run few seconds. UNLESS my mechanical lift pump goes kaput. If so then will bypass mechanical lift pump, with emergency pre-made fuel line I can install as needed. In that cause I will just set timer to let the pump run for hours when key is in position as below ..
1. Wire ONE RD key position, NOT Asc, NOT Off key position. YES or NO on SC??? its got fuel filter and few larger than average inline filters..... so maybe do not need on SC??? your thoughts??? buttt. then again if have to bypass mechanical lift pump for some reason then does that change anything???
- Technically. what will really happen here is in the correct key position based on above. it will send 12v to a step up converter. That step up converter will then send 24v to 24v timer and then... 24v fuel pump. Long story short... this was part of what (I thought) I had to do. (At time) Could only find a 24v pump that allowed full free flow thru it even when this pump is OFF AND also had 3/8 ID fittings so not to restrict fuel flow to something below specs of MB lift pump. . Most electric pumps do NOT allow much; if any, fuel to flow thru them when they are not powered.
2. Wire TWO is ground: The step up has a ground wire .. so could complete 12v path via Negative connection to something in power Box.
Device Three- This one a 12v generic fuel pump controlled via a 12v timer. It operates ONLY to clean/Polish the fuel in the tank. NOT connected to engine. Just pulls fuel from tank thru a filter AND water separator then right back to the tank. Will likely run 15min... thoughh.... I may put a 12v solar panel on Jeep and let it run 30 min. soo
1. Till I get a solar panel. Key in RD position only activating the timer. Disconnected in Off, SC and Asc. Most my uses of Jeep are 15min drive or more.
2. AFTER install solar panel.
A) option- Key in RD activates timer set to 30min. Key in Off does not stop timer if 30min not up when stop vehicle. Similar to electric radiator cooling fans. So would that be a second power wire from???? that bypasses into #1? for this device?? or is that even possible? Purchase/add in a different kind of relay like ones used on elec. radiator fan and power that relay from the key RD?? Not sure how stay on thermal switched fans get powred.
(B) option- If (A) is not possible. or if it is just easier way to go about it..... technically could use the timer to have it run 30 min every two days??? for example. Sooooooo that would mean Swap this devices #1 power to full time power leaving the timer to control the on/off of pump. BTW chose 30 min cause that is about how long it would take to cycle full tank of fuel thru the polish filter. yeah I know. over kill.
3. Wire THREE is ground and I did run one all the way up to the Power Center... so could disconnect Negative as an option
PS- this will be daily driver rain snow or storm. And/or be pulled behind live in camper. (next HUGE project)
Notes and Reminder again: No CPS but can put it back. Computer ASD (auto shut down) is there but I do NOT know if it is disabled on underside of this power box or what). I will be adding a Winch. The alternator has a remote regulator not connected to Jeep computer.
photo's are my under hood box and cover. (2002... or is it 03. I forget) Will post this first then come back and add pictures
Anyway. Here goes. Ohhh. and to confuse things from get go:
A. This Jeep was converted to a diesel by previous owner. Their grafting of Mercedes Glow Plug wiring into the Jeep system worked. Dash Worked except Tach. I am swapping this clapped out engine for a rebuilt one of same kind/model mercedes. Started in Nov. but got to cold. Restarted project when retired in June.
B. there is no CPS (crank position sensor) it is cut off. Previously it worked sorta. CPS was there but just dangling off to the side and not on the Jeep Transmission. I cut it off since it just jangle dangled by the hot exhaust. Can reconnect if it needs it to make the computer happy (or jumper it ... suggestion how?) Computer only gives me dash stuff except Tach.
First-. embarrassed to say do not know how many key positions there are on the TJ. Actually searched the inter-webs but didn't find it.... is there even an accessory? Ill Include it just in case. For lack of not knowing the TJ world Terms will use:
. SC (Start/Crank),
. RD (Run Driving),
. Asc (Accessories operate in keyed Asc. position, when engine is not running, but NOT when key is off) ,
. Off (off- key in or out)
Second/Third. Don't care if tap into a Fuse slot or remove an unused relay and tap slot(s) there. Do not need to go thru a Jeep fuse. Do not Want to piggy back on a functioning relay such as there is a fuel pump relay in Power box still. Do not know why; there was no 12v pump in conversion. Was it there to keep computer happy? Previous builder just left it as a spare? he was lazy??. I could remove it and tap something there??
Four- I am adding some fuel pump(s) this time though... again it had no elec. fuel pump in previous running diesel conversion arrangement. Engine has a mechanical lift pump. I could; if it would still keep computer happy, remove Jeep fuel pump relay and use one of its slots as a Tap in point... or off its fuse home???
Five- All the timers I speak of below have a relay built in.
Six- the two timer's i am adding do NOT need positive power in key off position to keep memory of their settings (supposedly). Chinese directions hard to decipher butt other's seem to report that this is the case.
Seven- BTW: Am putting a separate inline-fuse for each below so only 12v positive (or negative?) is needed at the right Key switch position(s) for each device below:
Device One- (Mercedes glow plug relay / diesel swap). PRIORITY. NEED THIS NOW. It has two hot wires. I would wire this back like it was. butttt. the so called PERMANENT ink faded on my labels and I can no longer read them. Thought I had pictures. but nooo. (did I say Im stupid to have thought double redundancy would be enough)
1. Wire ONE is to be wired to +12v at key RD position- assuming RD is prior to SC in key position like it always is duhhh. In normal use; this MB relay.... with key in position to power it; its own internal timer does it's Glow hot plug thing. At chime. you move key to SC to start the engine or I can push a button to have it start the timer again on extra cold days that I want to glow the plugs twice. It's internal timer will switch off relay depowering the Glow Plugs.....if I understand correctly how this works there is more to it (there is thermal switch in there too). Do NOT want this powered in Asc key position or Off position.
2. Wire TWO provides 12v during SC . This delay's (skips past?) the timer. Timer resumes after engine starts (if any time left) and key is back to RD. Likely OEM mercedes did this way cause all their other items switched off during crank to leave battery only getting draw from starter and glow plugs???. Do NOT want this powered 12v in Asc key position (jamming to tunes looking at a sun setting atop a mountain) or Off key position.
3. It has a ground wire but mercedes did not use that as a switchable thang.
Device Two- Inline Electric Primer lift pump / Emergency drive lift pump. Same pump for either. Once best power source found based on below , power will first go to a timer I can program. In normal use this likely will only be set to run few seconds. UNLESS my mechanical lift pump goes kaput. If so then will bypass mechanical lift pump, with emergency pre-made fuel line I can install as needed. In that cause I will just set timer to let the pump run for hours when key is in position as below ..
1. Wire ONE RD key position, NOT Asc, NOT Off key position. YES or NO on SC??? its got fuel filter and few larger than average inline filters..... so maybe do not need on SC??? your thoughts??? buttt. then again if have to bypass mechanical lift pump for some reason then does that change anything???
- Technically. what will really happen here is in the correct key position based on above. it will send 12v to a step up converter. That step up converter will then send 24v to 24v timer and then... 24v fuel pump. Long story short... this was part of what (I thought) I had to do. (At time) Could only find a 24v pump that allowed full free flow thru it even when this pump is OFF AND also had 3/8 ID fittings so not to restrict fuel flow to something below specs of MB lift pump. . Most electric pumps do NOT allow much; if any, fuel to flow thru them when they are not powered.
2. Wire TWO is ground: The step up has a ground wire .. so could complete 12v path via Negative connection to something in power Box.
Device Three- This one a 12v generic fuel pump controlled via a 12v timer. It operates ONLY to clean/Polish the fuel in the tank. NOT connected to engine. Just pulls fuel from tank thru a filter AND water separator then right back to the tank. Will likely run 15min... thoughh.... I may put a 12v solar panel on Jeep and let it run 30 min. soo
1. Till I get a solar panel. Key in RD position only activating the timer. Disconnected in Off, SC and Asc. Most my uses of Jeep are 15min drive or more.
2. AFTER install solar panel.
A) option- Key in RD activates timer set to 30min. Key in Off does not stop timer if 30min not up when stop vehicle. Similar to electric radiator cooling fans. So would that be a second power wire from???? that bypasses into #1? for this device?? or is that even possible? Purchase/add in a different kind of relay like ones used on elec. radiator fan and power that relay from the key RD?? Not sure how stay on thermal switched fans get powred.
(B) option- If (A) is not possible. or if it is just easier way to go about it..... technically could use the timer to have it run 30 min every two days??? for example. Sooooooo that would mean Swap this devices #1 power to full time power leaving the timer to control the on/off of pump. BTW chose 30 min cause that is about how long it would take to cycle full tank of fuel thru the polish filter. yeah I know. over kill.
3. Wire THREE is ground and I did run one all the way up to the Power Center... so could disconnect Negative as an option
PS- this will be daily driver rain snow or storm. And/or be pulled behind live in camper. (next HUGE project)
Notes and Reminder again: No CPS but can put it back. Computer ASD (auto shut down) is there but I do NOT know if it is disabled on underside of this power box or what). I will be adding a Winch. The alternator has a remote regulator not connected to Jeep computer.
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