Heater Relays - quick question
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Heater Relays - quick question
One of my relays is working one is not, that is I get power when the "wait to start light" comes on the rear one towards the firewall.
The other relay (the forward one) isn't sending power thru it even though the little plugs on top are hot and the battery supply side is also hot.
I'll assume it's bad...
What does this heater relay power exactly? Should the little plugs on the top remain hot all the time when cold out? Just turning on the key not starting engine.
Should I just replace it with a cheapo relay like a ford starter relay? If so then do I wire both plugs together?
The other relay (the forward one) isn't sending power thru it even though the little plugs on top are hot and the battery supply side is also hot.
I'll assume it's bad...
What does this heater relay power exactly? Should the little plugs on the top remain hot all the time when cold out? Just turning on the key not starting engine.
Should I just replace it with a cheapo relay like a ford starter relay? If so then do I wire both plugs together?
#2
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It's quite common for one of the relays to fail. It's the contacts that fail, so even though the relay is working electrically, the current isn't going through. I always get the factory replacements from Dodge- both relays come together with the bracket. I prefer the clean "factory" look. I wouldn't wire both grids together with one relay. The reason is that the PCM cycles one relay at a time for the post heat cycle. Both at the same time would be hard on the charging system when the truck is running.
#4
I used Ford starter relays on mine. It was suggested by Infidel. They only cost about $7.00 and I think they are better. Ask for the older model ones. They look just like the OEM ones but they are bigger.
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I didn't mean wire everything onto one relay
On the forward most relay there is two small wires with plugs on them that snap onto the top of this relay along with the two heavy leads. If I am not mistaking a Ford relay only has one small wire to activate the relay.
My question was, do I wire both of these small wires together?
if the OEM ones arn't too much I think I may just go with those and mail order them. I'm stuck at work and cannot make it to a parts store
On the forward most relay there is two small wires with plugs on them that snap onto the top of this relay along with the two heavy leads. If I am not mistaking a Ford relay only has one small wire to activate the relay.
My question was, do I wire both of these small wires together?
if the OEM ones arn't too much I think I may just go with those and mail order them. I'm stuck at work and cannot make it to a parts store
#6
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I didn't mean wire everything onto one relay
On the forward most relay there is two small wires with plugs on them that snap onto the top of this relay along with the two heavy leads. If I am not mistaking a Ford relay only has one small wire to activate the relay.
My question was, do I wire both of these small wires together?
if the OEM ones arn't too much I think I may just go with those and mail order them. I'm stuck at work and cannot make it to a parts store
On the forward most relay there is two small wires with plugs on them that snap onto the top of this relay along with the two heavy leads. If I am not mistaking a Ford relay only has one small wire to activate the relay.
My question was, do I wire both of these small wires together?
if the OEM ones arn't too much I think I may just go with those and mail order them. I'm stuck at work and cannot make it to a parts store
The Ford relays may be slightly better than the OEM preheater relays, but I have never seen an OEM relay cause trouble before 120 000 miles, so it's not a big issue.
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The can't be both ground, I used a tester light and both showed positive hot.
edit: Or my ground wire wasn't working ??? and it was pulling ground thru my tester? I'll check this further when I get home.
In case others are looking at this problem the OEM part number is 56026842
Wholesale $53.13. If you call your local dealer they'll charge $72.00. I'll mail order it wholesale.
took me a bit to find it on the net, I think I'll just order the OEM replacement. They come in a kit and it replaces both relays together
edit: Or my ground wire wasn't working ??? and it was pulling ground thru my tester? I'll check this further when I get home.
In case others are looking at this problem the OEM part number is 56026842
Wholesale $53.13. If you call your local dealer they'll charge $72.00. I'll mail order it wholesale.
took me a bit to find it on the net, I think I'll just order the OEM replacement. They come in a kit and it replaces both relays together
Last edited by greasy; 11-25-2006 at 12:14 PM. Reason: had a second thought
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#8
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If I am not mistaking a Ford relay only has one small wire to activate the relay.
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The leads are always hot. The PCM provides the ground while the heater grid is cycling. I wired my grounds to a toggle switch so I can turn them on or off manually. My reasoning is that once the engine is running there is no benefit for the grids to cycle on.
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also said I didn't start the engine, I was just cycling the pre-heaters on and off to find the problem.
I think the 79 ford ones will work, cheap I like. I used to use them all the time for running big KC daylighters
I think the 79 ford ones will work, cheap I like. I used to use them all the time for running big KC daylighters
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Was it necessary to turn the ignition key on and off to keep power to the relays? Even without starting the engine the PCM will cycle the grid heaters off.
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