# The resistance of 2 coils is 25 ohms when connected in parellel and 6 ohms when connected in series. determine the resistance of the 2 coils? (i nedd the working also)

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Equation for series R1 + R2 = 6 equation for parallel 1/R1 + 1/R2 = 1/25 substitute first equation for R2 in second equation: 1/R1 + 1/(6 - R1) = 1/25 I will leave the algebra solution to you.

Posted on Oct 01, 2010

• Al Kupchella Oct 01, 2010

Ah, but this was a trick question, as you might have discovered there is no solution. This is because two resistors in series cannot have less resistance than those same two resistors in parallel.

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## Related Questions:

### I have 2 duel 12' 2ohm sub's and a blackmore bac m-50 2000 watt 4ohm amp and was wondering how to wire. Thanks!

boz word of caution is to be heeded. with 2x2 ohms per speaker, you can only use one, with the voice coils ran in series to increase the resistance to 4 ohm . take a single driver, and use the series wiring on with both of the 2 ohm voice coils.

wire positive from the amp into positive of one voice coil, then the negative of that voice coil to the positive of the second voice coil 9bridging with 6 gauge or so, as was also mentioned by a previous user), then lead the negative of the second voice coil back to the amp's negative terminal.

Jun 01, 2015 | Car Audio & Video

### Firing order coil pack 2000 ford explore 5-0

Firing Order is 1 3 7 2 6 5 4 8

JF: Integrated Ignition Coil On Plug Coil 1 Through 10 Failure

2000 PCED On Board Diagnostics II

SECTION 5: Pinpoint Tests

Procedure revision date: 01/31/2001

JF: Integrated Ignition Coil On Plug Coil 1 Through 10 Failure

? JF: Introduction

JF1 DETERMINE WHICH COIL IS NOT FIRING

Note: Electronic ignition engine timing is entirely controlled by the PCM. Electronic ignition timing is NOT adjustable. Do not attempt to check base timing. You will receive false readings.

• Determine which coil is not firing using information from Pinpoint Test JB or DTC and the table at the beginning of this pinpoint test.

• Record cylinder, coil and PCM pin number from the table.

Have the cylinder number, coil driver and PCM pin number been recorded?

Yes

No

GO to JF2.

To obtain required information, GO to JF1 and REPEAT.

JF2 DTC P0351, P0356, P0357: CRANKSHAFT POSITION SENSOR FAILURE
Are any of the above listed DTCs present?

Yes

No

GO to JF3.

GO to JF4.

JF3 CHECK RESISTANCE OF CRANKSHAFT POSITION SENSOR

• Measure resistance of crankshaft position sensor.

Is resistance between 290 and 390 ohms (for LS8 between 900 and 1300 ohms)?

Yes

No

GO to JF4.

REPLACE crankshaft position sensor. COMPLETE Misfire Monitor Repair Verification Drive Cycle (REFER to Section 2, Drive Cycles).

JF4 CHECK FUNCTIONALITY OF SUSPECT COIL DRIVER (CD) CIRCUIT

• Disconnect suspect coil (determined from the table).

• Connect incandescent test lamp between IGN START/RUN and suspect CD circuit (determined from the table) at the coil on plug harness connector.

• Disable fuel pump by disconnecting inertia fuel shutoff switch.

• Observe incandescent test lamp while cranking engine.

Is the test lamp blinking consistently?

Yes

No

KEY OFF. GO to JF5.

KEY OFF. GO to JF6.

JF5 CHECK FUNCTIONALITY OF SUSPECT COIL

• Remove suspect coil (determined from the table) from spark plug.

• Connect an air gap spark tester 303-D037 (D81P-6666-A) or equivalent to a suspect coil.

• Reconnect suspect coil harness connector.

• Observe spark tester while cranking engine.

Is the spark present?

Yes

No

KEY OFF. INSPECT spark plug, REPLACE if necessary. GO to Z1.

KEY OFF. REPLACE coil. INSPECT spark plug, REPLACE if necessary. COMPLETE Misfire Monitor Repair Verification Drive Cycle (REFER to Section 2, Drive Cycles).

JF6 CHECK IGN START/RUN VOLTAGE TO SUSPECT COIL

• Key on, engine off.

• Measure voltage between IGN START/RUN circuit at the coil on plug harness connector and ground.

Is voltage greater than 10.0 volts?

Yes

No

KEY OFF. GO toJF7.

KEY OFF. LS6 and LS8: GO to B5.

All others: IGN START/RUN circuit fault. CHECK condition of related fuses/fuse links. If OK, REPAIR open circuit. If fuse/fuse link is damaged, CHECK IGN START/RUN circuit for short to ground. REPAIR as necessary. COMPLETE Misfire Monitor Repair Verification Drive Cycle (REFER to Section 2, Drive Cycles).

JF7 CHECK SUSPECT CD CIRCUIT FOR OPEN IN HARNESS

• Disconnect PCM.

• Measure resistance of suspect CD circuit between PCM harness connector pin (determined from the table) and coil on plug harness connector.

Is resistance less than 5 ohms?

Yes

No

GO to JF8.

REPAIR open circuit. COMPLETE Misfire Monitor Repair Verification Drive Cycle (REFER to Section 2, Drive Cycles).

JF8 CHECK SUSPECT CD CIRCUIT FOR SHORT TO VPWR IN HARNESS

• Key on, engine off.

• Measure voltage between suspect CD circuit at the PCM harness connector (determined from the table) and ground.

Is voltage less than 1.0 volt?

Yes

No

KEY OFF. GO to JF9.

KEY OFF. REPAIR short circuit. COMPLETE Misfire Monitor Repair Verification Drive Cycle (REFER to Section 2, Drive Cycles).

JF9 CHECK SUSPECT CD CIRCUIT FOR SHORT TO GROUND IN HARNESS

• Disconnect scan tool.

• Measure resistance between suspect CD circuit at the PCM harness connector (determined from the table) and ground.

Is resistance greater than 10,000 ohms?

Yes

No

GO toJF10.

REPAIR short circuit. If symptom or DTC is still present, GO to JF11 to check for damaged coil, otherwise COMPLETE Misfire Monitor Repair Verification Drive Cycle (REFER to Section 2, Drive Cycles).

JF10 PERFORM INTERMITTENT TEST ON SUSPECT CD CIRCUIT HARNESS

• Connect digital multimeter between suspect CD circuit at the PCM harness connector (determined from the table) and CD circuit at coil on plug harness connector.

• Wiggle and bend CD harness from PCM harness connector to coil on plug harness connector.

Did resistance fluctuate during wiggle test?

Yes

No

REPAIR intermittent fault in harness. COMPLETE Misfire Monitor Repair Verification Drive Cycle (REFER to Section 2, Drive Cycles).

REPLACE PCM. (REFER to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM)). If symptom or DTC is still present, GO to JF11 to check for damaged coil, otherwise COMPLETE Misfire Monitor Repair Verification Drive Cycle (REFER to Section 2, Drive Cycles).

JF11 CHECK SUSPECT COIL FOR DAMAGE

• Remove suspect coil (determined from the table) from spark plug.

• Connect an air gap spark tester 303-D037 (D81P-6666-A) or equivalent to a suspect coil.

• Disable fuel pump by disconnecting inertia fuel shutoff switch.

• Observe spark tester while cranking engine.

Is the spark present?

Yes

No

KEY OFF. INSPECT spark plug, REPLACE if necessary. GO to Z1.

KEY OFF. REPLACE coil. INSPECT spark plug, REPLACE if necessary. COMPLETE Misfire Monitor Repair Verification Drive Cycle (REFER to Section 2, Drive Cycles).

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### How do you check resistance through the heater coil?

To that defrost heater
set the meter to lowest ohms setting
follow wires that connect to heater up to the top of freezer coil
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place meter leads on the the 2 wires for the heater
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Hi there,
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PICK-UP COIL (HEI)

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### How to hook up 2 10 inch speakers

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Sep 08, 2008 | Boss IQ 3KD.1 Car Audio Amplifier

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