Starting problem
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Starting problem
Hi,
I have a starting problem. If I leave the car for a few days and turn the ignition the car refuses to start. I thought it was a parasitic draw at first but last night I checked the battery voltage and it read 12.4V which is more than enough to start the car. Strangely, I’m able to start the car via the diagnostic plug tripping terminals 11 and 14. The forums tell me that it is likely that starter switch is at fault, but I had it replaced 2 years ago. I know that if I fully charged the battery the car will start no problem. So, is the problem the starter or is there something else which may be at fault?
Anybody out there able to help me? Any assistance grateful received as usual.
1987 BMW 635CSI
I have a starting problem. If I leave the car for a few days and turn the ignition the car refuses to start. I thought it was a parasitic draw at first but last night I checked the battery voltage and it read 12.4V which is more than enough to start the car. Strangely, I’m able to start the car via the diagnostic plug tripping terminals 11 and 14. The forums tell me that it is likely that starter switch is at fault, but I had it replaced 2 years ago. I know that if I fully charged the battery the car will start no problem. So, is the problem the starter or is there something else which may be at fault?
Anybody out there able to help me? Any assistance grateful received as usual.
1987 BMW 635CSI
Chris,Chris Wright wrote:Well, if you have the Auto tranny, jumping pin 11 and 14 in the diagnostic plug does bypass the start relay behind the drivers kick panel. Perhaps the contacts are dirty and not passing full voltage?
If I may ask, what does this relay do? More than one function?
Bill
'87 635csi, 5sp man, dk blu on pearl beige
'88 635csi, auto, black on grey
'63 BMW Isetta
'75 XJ6C, 2dr, warm 350
'86 XJ6, th700r4
'75TR6
'64 Olds 88 conv
"68 T120 Bonneville
'88 635csi, auto, black on grey
'63 BMW Isetta
'75 XJ6C, 2dr, warm 350
'86 XJ6, th700r4
'75TR6
'64 Olds 88 conv
"68 T120 Bonneville
The start relay is only on Automatics and is only energized when the gear shift is in park or neutral so the car won't start in gear. It sets inline between the ignition switch and the starter.slofut wrote:Chris,Chris Wright wrote:Well, if you have the Auto tranny, jumping pin 11 and 14 in the diagnostic plug does bypass the start relay behind the drivers kick panel. Perhaps the contacts are dirty and not passing full voltage?
If I may ask, what does this relay do? More than one function?
Bill
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- Posts: 66
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Jumped terminals 30 and 87 on the start relay suggested by Chris in a past post and still the car won't crank. Does this mean that the ignition switch is faulty (despite it being replaced a couple of years ago)? or is there a switch within the auto shift mechanism I now should be checking. Car still cranks no prob jumping at the diagnostic plug.
thoughts appreciated
thoughts appreciated
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Agree with Ron. Maybe the battery is on the point of failing and won't hold a sufficient charge to get things moving - even though it may show more than 12 volts. Voltage doesn't always mean the battery's good!ron wrote:Try a NEW battery.blackbirdxx wrote:Just to reiterate, if I fully charge the battery, the car cranks no problem.
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This is a prime example of why you should LOAD TEST both the alternator and the battery when a low amperage situation is suspected. They can both check good with a voltmeter, but fail miserably when a load is applied.
Ken Kanne
'84 633CSi "Sylvia"; '85 635CSi "Katja";'85 325e "Hazel Ann"; '95 M3 "Ashlyn"
'84 633CSi "Sylvia"; '85 635CSi "Katja";'85 325e "Hazel Ann"; '95 M3 "Ashlyn"
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I had a similar problem for about 2 years. It would ONLY start on jumping the diagnostic socket. Having replaced everything in the circuit I narrowed it down to the after-market immobiliser!
Once I removed that from the immobiliser/ alarm circuit I had no more problems.
Might be worth checking if you have an after-market system fitted.
Once I removed that from the immobiliser/ alarm circuit I had no more problems.
Might be worth checking if you have an after-market system fitted.
They are ALWAYS rustier than you thought!!!!!!
'85 M #228
'87 M #367
'88 High line.
'10 X5
‘84 Alfasud 1.5 ti
'85 M #228
'87 M #367
'88 High line.
'10 X5
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Dealing with a similar issue.
The M6 acted like it had a dead battery today. Plugged in a start booster and no dice. Plugged in an external battery (from the RV), still no dice. Messed with the positive lead and it started
I believe the problem was corrosion in the positive terminal. I will post up the end result, but replacing the connector on the positive lead looks to have fixed things.
Joseh Joseh
The M6 acted like it had a dead battery today. Plugged in a start booster and no dice. Plugged in an external battery (from the RV), still no dice. Messed with the positive lead and it started
I believe the problem was corrosion in the positive terminal. I will post up the end result, but replacing the connector on the positive lead looks to have fixed things.
Joseh Joseh
1987 M6 - My dream car