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Auto Theft Prevention/chapman lock


QUESTION: I have a 1973 Buick Centurion Convertible that has a Chapman lock.  The lock still works as far as locking the hood.  However, the cut-off mechanism which prevents you from starting the car with the key does not work.  I was told by a locksmith that the lock had used up its last adjustment and this feature could not be restored.  True or false?  If you think the lock can be fixed to restored the cut-off switch feature, how would I go about having you do the job?  I have not had any lock trying to find a new Chapman lock.


ANSWER: Hello,

Chapman has been out of business for close to 20 years. It was not a good alarm in its day, but dealers pt them on their GM vehicles. When repairing theft recoveries in the 80's and 90's, it was common to see the high beams shattered. This is the easiest way to disable a Chapman.

The best thing I would recommend is get rid of that Chapman hood lock, because one day, it will fail and the only way to get your hood open will be to drill the lock and you will not be happy.
Up grade with a Directed Electronics hood lock.
Then have a paging unit installed. No one pays attention to blaring sirens anymore. The pager letss you be contacted. Crimestopper makes a pretty cool paging unit.

I would also suggest updating the starter disable with a simple hidden starter disable switch. All too common, these kids these days installing alarms put the valet (alarm disable) switch or a starter interrupt switch under the dash. That is the first place a thief looks! Valet switches and starter interrupts should never be permanently mounted under the dash.

All you need for a starter disable is to get a single throw toggle and 10 or 12 g wire. I will assume the hood lock is already connected into the Starter wire at the column under the dash. You can take that 10 or 12 wire and cut in two. Attach to ends to toggle and the other two where the hood lock connected. Wrap this harness with black electrical tape. Tie wrap to harness for strong connection. Use your imagination where to put this switch. At the door sill? Under the seat etc. You can flip the switch while engine is running and it won't start until you flip the switch back. You do need a serious 2013 upgrade.

Good Luck!

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Appreciate your detailed response and have sent $20 donation today via PayPal.
Still have a specific question:  Can the Chapman Lock be repaired to re-activate the kill switch?  Locksmith said the problem is that the lock has used up its "last adjustment."

Hi Joe,

As you can tell in my answe about the dealer installed Chapman hood lock, I am not a fan of them. My answers are not boiler plate, but based on my 30 years experience with a product.
The reason I stated contact DEI is because in the 90's DEI went on a buying binge and bought out a majority of auto security manufacturers and I believe Chapman, as well as Mai Gard and so many others were bought out by DEI. They may even stock a brand new Chapman hood lock for you. Now, the link O am giving you is not from Directed, but supposedly you can get an answer in minutes. Its a start:|ga|1|HI+-+Electronics|Directed&J

DEI stands for Directed Electronics Incorporated. If you cannot get an answer from this link, try to contact DEI directly.
I will do everything I can do to assist you. Chapman was not a factory installed unit. It was dealer installed. So if you are trying to keep the car original, Chapman was not original equipment for the car. Chapman was after market, dealer installed.
As I said, I will do everything I can to assist you if you are dead set on this Chapman device. I do not know if the hood lock and keys are available, but if they are, DEI should have them.

Good Luck!

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Rob Painter, ASE, CFL, CFEI


My background in auto theft is extensive. I have been directly involved in the repair of over 10,000 theft recovered vehicles. I also do insurance investigation as to how a vehicle was last operated. My clients are insurance companies and attorneys. Was featured in the A & E auto theft documentary "Stealing Wheels" July 26, 2000. Has consulted with Daimler Chrysler steering column engineers to make their steering columns harder to defeat. Holds patent # 6,039,140 for 8 different variations to protect air bags from theft.


ROB PAINTER, ASE, CFL, CFEI Forensic Vehicle Component Analyst Diplomate, Board Certified Forensic Examiner ASE Certified Auto, Collision, Med/Hvy/Duty Truck Technician Certified Forensic Locksmith Certified Fire and Explosion Investigator Certified Vehicle Fire Investigator Certified Forensic Auto Theft Examiner Certified Auto Theft and Fraud Expert P.O. Box 190 Big Bend, WI 53103 Phone (414) 698-9696 Fax (262) 662-1352 As per federal court rules of evidence (702) (Daubert) my testimony has qualified me as: Auto Theft and Fraud Expert Forensic Vehicle Analyst Fire Origin and Cause Expert In the trial transcript of Holiday vs Progressive Insurance Company (March 12, 2002?Eugene, Oregon) with Holiday being my client-named ?the expert for experts.? BUSINESS EXPERIENCE Founder of the ?Forensic Institute of Auto Theft Analysis? (January 2002). This is the training school that will set the standards in determining the last operation of a reported stolen vehicle-burned or unburned. Much of my testing and procedures have been accepted as the guide for the forensic community. 1986 opened Auto Recovery Specialists Inc., providing exclusive repair of theft recovered and vandalized vehicles. The initial concept of the business was to return vehicles to their original shape before the theft, vandalism or fire. In 1987 bought the rights to the theft deterrent known as the ?Chicago Collar?. Duties include complete component replacement: dash, stereo system, interior, locks and coding, rebuilding steering columns, repairing and installing vehicle security system components (factory and after market), engine components, body repair, glass replacement, repair and service of air conditioning components, brake and suspension repair, and replacement, wiring harnesses etc. to return vehicle to pre-theft condition Complete reconstruction. During the past 17 years directly involved in the repair of over 10,000 theft-recovered and fire damaged Personally examined and rebuilt thousands of steering columns on both import and domestic vehicles Internationally acknowledged as expert in auto theft including court, consulting with insurance companies, attorneys and law enforcement. Consultant on steering columns, locks, stereo systems and vehicle security for Special Investigation Units for many large insurance carriers during the past eight years. Consulting services include but not limited to: How a vehicle was last operated (with or without keys in burned or unburned vehicles), Origin and Cause of vehicle fires, and vehicle defects. Provides services as a consultant and researcher to attorneys and insurance companies, and private industry throughout the US in cases related to vehicles. Has worked with crime prevention officers throughout the US establishing training programs designed to protect the public from becoming victims of auto theft. PATENT: 3/21/00 issued patent# 6,039,140 for 8 different variations of airbag anti-theft devices. PUBLICATIONS Currently authors articles and test reports on an ongoing basis for SIUs and the forensic/vehicle fire industry. Published author: (1,297 slide training course) Auto Theft/ Fraud Training Course) ?The Modern Forensic Approach to Auto Theft Investigation.? (January, 2001) Author: ?Variables to Be Considered In Vehicle Fire Investigation after Suppression.? (Insurance publication-November 2001) Author: ?Ford Magnesium Steering Columns and the Results to Ignition Components after a Fire?. Article for peer review from the fire and forensic community. (November 2001) Author: ?The Truth About GM VATS.? (Article) (November 2001) Author: ?The Truth About GM PASSLOCK TM? (Article) (November 2001) Author:? Auto Theft Investigation: Hollywood vs. Reality? (Article) (February 2001) For the John Cooke Fraud Report. Published author: (Manual) ?Forensic Vehicle Fire/ Arson and Auto Theft Investigation? (October 2000) Published author: (Article) ?Petty Claims? for the John Cooke Fraud Report (October, 1998) Published author (Manual) ?AUTO THEFT: LET THE TRUTH BE KNOWN!? (1998) (Previously distributed by Barnes & Nobel) Co-authored the investigation manual, ?Surreptitious Entry & Auto Theft & Burn & the Investigator.? (1999) Authored test questions on the subject of steering columns and vehicle security for CFL designation to be given by the International Association of Investigative Locksmiths. January, 2000 Published author: (Manual) ?Saginaw Steering Columns-What Has Not Been Told? Training manual for fire investigators. (March 2000) Published (Article) ?Beyond The Lock? (May 2000) Published Author: (Article) Fraud Defense Network-August, 2000 Edition-?Melting Steering Column Tests.? Published author: (Test Report) ?Burned Toyota Steering Column Testing to Determine How Last Operated?. Tool marks and procedures. (December 1999) Currently at the FBI Crime Lab in Washington DC and the US Army Crime Lab in Atlanta, GA for peer review. ACCOMPLISHMENTS Defeated the ?unstealable? Ford Securilock transponder system for a court case 10/10/00. They said it could not be done! Primary designer of a state of the art ?bait? car for a police department to catch car thieves. Worked with The National Highway Safety Transportation Administration and discovered a potential fire hazard on a vehicle and determined origin and cause of under hood fires on this type of vehicle. Featured as ?Auto Theft Expert? in the A & E auto theft documentary ?Stealing Wheels? that aired July 26, 2000. Contacted by Sears and Edelman Marketing to be a national spokesman for an anti theft device for vehicles. (November 1999) Invited to provide evaluation and consulting to steering column engineers at Daimler Chrysler Corporation in Auburn Hills, MI (10/19/99-10/22/99). The purpose of this project was to demonstrate how steering column locking mechanisms could be defeated without the use of a key and how to reinforce the columns against theft. Court Qualified as an Auto Theft Expert and my videos of defeating columns were also accepted by a Cleveland, Ohio Court in October 1999 as a valid piece of evidence. Contacted by Disney Touchstone Pictures for technical assistance in making the movie ?Gone in 60 Seconds? (March 1999) CONSULTANT FOR FOLLOWING ORGANIZATIONS ? Former contributor for The Insurance News Network (Auto theft and prevention) includes heading a forum for the public on how to protect their vehicles for 3+ years. ? Former editor and consultant for the public on matters involving auto theft and prevention 2000-2001 on the web at ? The Insurance Career Center (Auto theft and fraud). ? National Association of Investigative Specialists (Auto theft and fraud) ? Expert Find (Auto theft and fraud} TECHNICAL EXPERIENCE ? ASE (National Institute of Automotive Service Excellence) Certified in Auto: brakes, steering and suspension, engine repair, manual drive train and axles, air conditioning. Med/Heavy duty truck: gasoline engine repair, electrical/electronic components. Collision: elec.....

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