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Circuit 87 relay - 2003 Mercedes-Benz C-Class

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My 2007 f150 will not crank over I hear the relay click but there seems to be no power going to the solenoid. I replaced the relay and it started about 30 times now same prob any advice

What relay did you replace ? Starter relay ? Removing the relay you may have changed connector position in the fuse / relay box where the relay plugs into . Wiggle the relay see if that does anything . At the relay base jump pin's 30 & 87 with jumper wire , it should crank the engine over . If you look on the bottom of the relay you will see 4 set's of numbers 30 & 87 are load side of the relay . If you were to test with a voltmeter ,pin 30 would have Battery voltage ,Pin 87 goes to the S terminal on the starter solenoid . Pins 85 & 86 are the control side .When you turn the key to start B+ voltage goes through the run / start diode ,located in the AUX relay box 1 through the digital transmission range sensor to pin 86 of the starter relay ,pin 85 goes to the PCM .Where the PCM supply's a ground energizing the starter relay closing the contacts inside sending B+ voltage to the starter solenoid S terminal . Do you have a automatic trans or manuel ? Move gear selector to neutral , check out wiring diagram here Watch videos on youtube for basic electrical testing , voltage drop testing etc.... How to test a relay . Test the circuit ! How to voltage drop test starter motor circuit

Jan 21, 2017 | 2007 Ford F-150

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06 kia sportage 2.7 will not turn over. ..starter tested good, new neutral safety switch, please help

You need to test the electrical circuit , starter relay in the engine compartment . Is there B+ voltage at the smaller gage wire on the starter solenoid when cranking ( or trying to crank the engine ) ? Videos on you tube , testing from relay base ( where the relay plugs into ) Find the start relay in the fuse / relay box an pull it out . Look on the bottom of the relay , you should see four sets of numbers ! 30 , 87 an 85 , 86 . > 30 an 87 are the power side of the relay . 30 should have B+ voltage ,if not ignition #2 30amp fuse is blown . If there is B+ voltage you can take a jumper wirer ,an jump 30 to 87 > 87 goes to the starter solenoid . Jumping 30 to 87 will engage the starter .Checking for B+ voltage at pin 85 while trying to crank the engine, if there is b+ voltage you know the ignition switch is good an so is the transaxle range switch (neutral safety switch ) ! Does yours have a burglar alarm ? If so then there is an other part burglar alarm relay ! By testing at the relay you can tell which part of the circuit is bad ! Plus testing the heavier battery positive cable also needs to be done . Voltage drop testing the cables Starter Voltage Drop VEHICLE RELAYS Operation Diagnosis VEHICLE RELAYS Testing from the relay base This would cost you $86.00 to have this diagnosed at most auto repair shops. 1 hr .

Jul 29, 2016 | Kia Cars & Trucks

1 Answer

Radiator Fan Not Working Properly

If you see pin 87 you must see 30 ! 30 should have B+ voltage as will 86 . Pin 85 is to the engine computer ,PCM/ECM . If you jump to pin 85 you run the risk of frying the PCM on that circuit . A transistor inside the PCM is switched on when the engine temp gets to hot . The PCM supply's a ground for the control side of the relay energizing the relay an closing the contacts inside the relay sending B+ voltage from pin 87 to pin 30 to the fans ! Go to you tube an check out video on relay's an how they work .

Feb 04, 2016 | Cars & Trucks

1 Answer

Why can I not get power to the small wire going to the starter on my 2004 taurus

You need to know how it works before you can diagnose it. There is a starter relay in the under hood fuse/relay box .. This relay is controlled by the PCM - engine computer . Does you car have a anti-theft system ? a red light on top of the dash or a SECURITY light on instrument cluster ? Is the red light flashing fast when trying to start the car . If you find an pull the relay out an look on the bottom you will or should see four numbers . 30 & 87 , 85 & 86. You can test from the socket where the relay plugs in . PIN'S 87 & 85 should have B+ voltage . PIN 30 takes voltage from PIN 87 to start the vehicle , PIN 86 is the control from the engine computer . The PCM gives a ground on this circuit to energize the relay closing the contacts inside ,completing the circuit between B+ voltage on PIN 87 to PIN 30 to start the car.

Feb 04, 2016 | 2004 Ford Taurus

1 Answer

2011 chevy malibu, high beans not working. Where is fuse

From looking at a wiring diagram I 'd say the high beam relay in the under hood fuse / relay box would be the culprit . Because there is a separate fuse for both right an left hi beam lamps . Or the hi / low beam switch is bad or the BCM - body control module is not energizing the high beam relay . If you pull the hi beam relay out of the fuse box an look on the bottom you will see 4 numbers , 30 an 87 an 85 an 86 . 30 is battery voltage an 87 is the hi beam circuit . When energized the relay has contacts inside that close sending the battery voltage at pin 30 through pin 87 to the high beam fuse's. You could jumper those pins 30 to 87 an the hi beams should work , if there is no problem in the ground side of the circuit . Now 85 an 86 are the control side of the circuit . 85 has B+ an 86 goes to the BCM . When the BCM receives an input for hi beams it will give a ground inside the BCM to energize the relay .

Nov 13, 2015 | Cars & Trucks

1 Answer

Checked batt and starter have no dash lights only check engine starter will not even click

If your check engine light is on you should have it checked for DTC'S - diagnostic trouble codes ! An there is no SECURITY light lit on the instrument cluster ? In the underhood fuse / relay box is the CRANK RLY , this relay energizes the starter ! If you pull the relay out of it's socket you'll see four terminals or pin's what ever you like . You'll also see four numbers 85-86, 30-87 . 30 an 87 are the starter side circuit . 30 should have battery voltage if tested with voltmeter or a test light , 87 goes to the S terminal at the starter solenoid . 85 an 86 are the control side circuit , one should have battery voltage an the other is control from the PCM/ECM .If you can use a volt ohm meter you can see what is missing to further you diagnosis , voltage , control ! You mite want to do a voltage drop test of the starter circuit - battery cables ! Check fuse PCM/ABS 10amp left I/P fuse box an PCM (crank) fuse 10amp left I/P fuse box .If you haven't done this type of thing before you may want to take to a ASE certified repair shop ! Here I will post a video on relays ! VEHICLE RELAYS Operation Diagnosis

Jul 28, 2015 | 2005 Chevrolet Monte Carlo

1 Answer

Changed fuel pump relay and fuse. still no fuel

What make , model an year vehicle ? Did you check for Battery + voltage at the fuse an relay FIRST ? You test before replacing parts . Take a volt meter an measure for voltage at the fuse then at the relay ! There are four pins on the relay an four holes the relay plugs in two , Two of these holes should have Battery voltage , One is the control from the engine computer that energizes the relay coil . The last hole is the wire that goes to the fuel pump. You could jump pins 30 to 87 , if you look on the side there is a diagram . Also on the bottom sometimes the pins are marked 85 an 86 an 30 an 87 ! The last two 30 an 87 are the load side , the fuel pump side . You could jumper 30 to 87 ,direct power to the fuel pump ! You have to test the electric circuit ! GM Fuel Pump Relay Testing How do you know you have no fuel pressure ?

Mar 14, 2015 | Cars & Trucks

1 Answer

How do i jump my asd relay on a 03 dakota i have jumped the 87 and 30 and it is a no start situation

the sequence is in two circuits 1. pin 30 power enters relay-pin 87 power leaves relay to ign coil . 2. pin 86 power enters relay-pin 85 power exits to the PCM which then provides the earth for the ASD so you need to check the second circuit pins 86 & 85, if these are not recieving/sending power then the PCM wont provide the earth, if they are providing power then the problem lies with the PCM, hope this is of help

May 03, 2014 | Cars & Trucks

1 Answer

I have check engine error codes 11, 12 on my 95 grand cherokee limited the engine wont start just keeps turning over

Code 11 means no distributor reference signal detected during cranking. Check the circuit between the Distributor and PCM (computer). Also, keep in mind the following operations/tests apply to these relays only: Automatic Shutdown (ASD) , Fuel Pump and Ballast Bypass. For operations/tests on all other relays refer to the appropriate test.

The relay terminal numbers can be found on the bottom of the relay.
Terminal number 30 is connected to battery voltage and can be switched or B + (hot) at all times.
Terminal number 87A is connected (a circuit is formed) to terminal 30 in the de-energized (normally OFF) position.
Terminal number 87 is connected (a circuit is formed) to terminal 30 in the energized (ON) position. Terminal number 87 then supplies battery voltage to the component being operated.
Terminal number 86 is connected to a switched power source.
Terminal number 85 is grounded by the Engine Controller.

Remove relay before testing.
Using an ohmmeter, perform a resistance test between terminals 85 and 86. Resistance value (ohms) should be 75 ±5 ohms for resistor equipped relays.
Connect the ohmmeter between terminals number 87A and 30. Continuity should be present at this time.
Connect the ohmmeter between terminals number 87 and 30. Continuity should not be present at this time.
Use a set of jumper wires (16 gauge or smaller). Connect one jumper wire between terminal number 85 (on the relay) to the ground side (-) of a 12 Volt power source.
Attach the other jumper wire to the positive side (+) of a 12V power source. Do not connect the jumper wire to relay at this time.

CAUTION: Do not allow the ohmmeter to contact terminals 85 or 86 during these tests. Damage to ohmmeter may result.

Attach the other jumper wire (12V +) to terminal number 86. This will activate the relay. Continuity should now be present between terminals number 87 and 30. Continuity should not be present between terminals number 87A and 30.
Disconnect jumper wires from relay and 12 Volt power source.

If continuity or resistance tests did not pass replace relay. The Powertrain Control Module (PCM) and connector are located in the engine compartment, mounted to the inner fender, next to the air cleaner housing (click image fo zoom).
DTC 11 - No reference signal during engine cranking. No camshaft reference signal was detected during engine cranking.
DTC 12 - Battery disconnect. Battery input to PCM disconnected during last 50 key starts.
DTC 42 - ASD relay control circuit. An open or shorted condition detected in the auto shut down relay circuit.


Hope helps.

Jun 06, 2011 | Jeep Grand Cherokee Cars & Trucks

1 Answer

Need to know the location of the fuel pump relay for a 89 560 SEL.

behind the rear firewall there should be several relays. one is an over voltage protection relay and is fused. there should be 2 black 16 pole(not all the poles are used)relays. 1 will say klima on it-that is your climate control relay. the other is your fuel pump relay-it may say kick down because the trans kick down solonoid receives it's power from that relay as well. circuit 30 is your hot all the time circuit and circuit 87 is your consumer(fuel pump). 31 is ground and 15 is hot with the key on. do not bridge anything else but circuit 30 and 87. use a fused bridge wire and see if the fuel pumps work. I hope I have been helpful

Jun 18, 2009 | Mercedes-Benz 560-Series Cars & Trucks

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