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Meaning of relay acronyms: H-LP, E/G, DIM etc

Legend to Codes E/G - Main is the relay for the Radiator fans. EFI - Is the electronic fuel injection relay. DIM - is the headlight dimmer relay. H-LP - is the headlamp relay. MG/C - is ...
Ben's user avatar
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7 votes
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Positions of relays in fuse box of Honda Accord 2003

The relays are the same They should be interchangeable. Here is a parts diagram. They control components of the fuel system.
DucatiKiller's user avatar
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How can I extract this relay?

Just pull the relay out from the terminal block. There are 4 or 5 terminals which grip tightly so that the current does not cause any heating damage.
Solar Mike's user avatar
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5 votes
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What is the formula to determine a relay for aftermarket lights?

You need to know up front what the Amperage of the lights are in the first place and work from there. In the case of the light in the link is has a 72W draw on it. @ 12vdc, this calculates to 6Amps ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
4 votes

Positions of relays in fuse box of Honda Accord 2003

It is very likely that the two relays will be the same configuration, since their positions can be interchanged. But, there could be differences. One thing you can do to check is to read the part ...
dlu's user avatar
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Very Strange Starting?/Electrical Issue

The problem lies in your connections to the battery or ground. I'm not sure how you tested them, but from your description, this is a classic case of losing connectivity from either the ground strap ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
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What are the common causes of inconsistent/dead flashers?

If they work inconsistently, it may indicate bad electrical contact. In older cars the technique used for the on/of nature of flashers, is based on heat caused by current. If there's not enough ...
Bart's user avatar
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3 votes
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Brake lights no longer work on a Volvo V70

My suggestion would be to chase the wiring directly rather than trying to identify all the parts of a system your mechanic did not even identify for you. If possible, find an electrical diagram for ...
cdunn's user avatar
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3 votes
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Correct Relay Splicing Methodology (Backup Camera & Reverse Wire)?

Neither of those diagrams would work the way you want them to. In diagram one power never reaches the lights as up to pin 86 is grounded. In diagram two power reaches the lights, but pin 86 is never ...
Ben's user avatar
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3 votes

Correct Relay Splicing Methodology (Backup Camera & Reverse Wire)?

You can't do that either way you tried. You need power +86 from the reverse wire, and a suitable ground path +85 for the other side of the coil. You'll have to add wire and find bare metal or ...
SteveRacer's user avatar
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Golf MK4 Window Motor Click and Window wont open

Thank you guys for your advices. Yesterday i bought 2 regulators for the 2 doors. Now it works perfectly. 2 days ago the driver's door stuck in central locking and the window motors circuit doesnt ...
edisonmecaj's user avatar
3 votes

Starting an automatic for the lazy mechanic

If your starter relay is similar to this relay on the Farnell website. Then you need to connect the pins labelled 87 and 30 together.
HandyHowie's user avatar
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Why does a relay not short the battery?

No, you will not be shorting the battery. The relay COIL, for a 12V relay, is designed so that when it's energized (i.e. connected between 12V and ground) will only pass enough current to close the ...
jwh20's user avatar
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2 votes

Standard mounting screw for vehicle relay

There is no standard fitting for relay mounts, and so thus the generic hole. Hella makes a 20/40 amp mini SPDT that has a metal bracket rather than a plastic bracket. They also sell connectors with ...
timbo's user avatar
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2 votes

How many amps should my car pull while it is turned off?

I've come across this many times. The acceptable current draw should be around 0.03Amps. If that can't be achieved upto 0.075-0.1 can be acceptable if the vehicle is driven most days.
Newbie Noob's user avatar
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Diagnosing fuel pump relay on 2004 Acura TSX

The power in the in pins 1 and 3 proves that fuse 19 is OK and that the PCM will turn on PGMFI relay #1 and further that said relay will supply power to the fuel pump relay (PGMFI relay #2). It does ...
Fred Wilson's user avatar
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2 votes

Motorcycle won't start without jumping the solenoid

The "solenoid trick" pretty much guarantees that the solenoid is good. When you short it with the wrench you're simulating a start signal on the small terminal. When you do that the solenoid does its ...
dlu's user avatar
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2 votes
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Subaru Impreza rear wiper relay?

Do you mean you're unsure whether the part number is 12V5B-1T or 642N? Odds are good it is one of those. Try searching for each (e.g., feed "12V5B-1T relay" to the Google) and see what you get. It is ...
dlu's user avatar
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2 votes

What are the common causes of inconsistent/dead flashers?

Common Issues - Poor Grounds Moisture either in the bulb housing (causing a short) Moisture around the fuse box (or where ever the flasher relay is located) Incorrect bulb type/material (some older ...
16volt's user avatar
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2 votes
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Help tracking down a battery drain issue on a 2007 Vauxhall Corsa

If the relay is not defective, then I would check for any chaffed or damaged wires under the bonnet or under the dash - this could cause the relay to energise. One other possibility is someone has mis-...
Solar Mike's user avatar
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2 votes

Why do we use a relay and switch to control on/off of horn circuit instead of using a simple swtich?

You really aren't understanding how a relay works or what it does. It states right in the quote that the control wire can only handle .25A and is very thin. The horn itself may require 24A or more. ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
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How to replace the door lock relay on Honda CRV 2005

The door lock/unlock relays are built into the multiplex unit on that year CR-V and are not serviceable (See Figs. 1 & 2). To replace it you'd either have to replace the whole multiplex unit or ...
Ben's user avatar
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2 votes
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Honda Jazz 2007 - One headlight not working when dipped. Same bulb for full beam is OK, other light for dipped is OK

There are three possibilities: 1) a defective bulb, each bulb has two filaments so while the high may be fine the low may have failed 2) there is a blown fuse for the RH low beam - some cars have ...
Solar Mike's user avatar
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2 votes

Is it possible to charge a small auxiliary battery with the alternator?

Instead of using the alternator, use a charger appropriately sized to charge the AGM battery. The charger would run off of the car battery and the alternator would charge the car battery. 6A works out ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
2 votes

What should be the expected voltage on pin 30 of a starter relay?

It should have battery voltage going into the #30 pin. This is where the relay gets its power to go out through #87 to the device getting power. Before you got replacing the relay, ensure you're ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
2 votes
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Why would overheating relays cause problems when trying to start a car?

Honda had a pretty big problem with their relays. Once the interior of the vehicle heated up, the small circuit board in the relay would expand and the tracings on the board would open enough to cause ...
user9181's user avatar
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2 votes

Relays in series connection?

Both relays need 12V to reliably operate the coil, in series they will only get 6V. So, no this is not a good idea. The best is to connect them in parallel and they will operate at the same time.
Solar Mike's user avatar
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2 votes

Automotive relay pin numbers

The numbering system is given in DIN 72552. 1 = 85 (can probably be swapped with 86) 2 = 86 Since it's just a normally open contact ... 3 = 30 I would call this 87 as it is the 'hinge'/common. 5 = ...
Transistor's user avatar
2 votes
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Any benefits of a relay over a dead mans switch between two 12V batteries apart from preventing discharge of starter while car is off?

30 amp rating is the capacity of the relay, take it past that rating and it burns up, go for the dead mans switch or a commercial battery Isolator, example here Generally you want the amp rating ...
Moab's user avatar
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